Boss-Altering Consequence

What's worth more?

"We actually have a power core dedicated to charging Tor's exoskeleton right here, but I doubt we'll have to use it. If you were to mess with that terminal over here, it means Tor will be FULLY charged for battle, absolutely no punches held."

— Iji, logbook by Komato Berserker 05629-92837-50068

A Boss-Altering Consequence is a catch-all term for when a sidequest, choice, item, or other action affects a Boss Battle in a unique way. They're not required to beat the boss itself, but if you fulfill the right objectives, they'll often make a boss easier or harder. For example, if there's a secret weapon that only one specific boss is weak to, then you may have the option to obtain it beforehand to make the boss battle easier. Or maybe you can obtain something that will give you a unique buff against the boss. A Boss-Altering Consequence can also change the boss' moveset, or they can alter the number of bosses you must face off against in a single fight. Sometimes, it may not necessarily affect the boss's difficulty, but it may affect its aesthetics, like its appearance or dialogue, usually as an Easter Egg or Developer's Foresight.

Occasionally, the Boss-Altering Consequence can even happen during the boss fight itself. Maybe if you fight a boss a certain way, something interesting or beneficial will happen later on. Perhaps there's something in the area that you can potentially use to deal major damage to the boss. Or perhaps you can talk to the boss so that you can get an advantage if you make the right dialogue choices.

This is different from Level Grinding, changing the difficulty setting, or simply using any regular abilities, items or equipment against the boss, as the Boss-Altering Consequence specifically affects boss battles alone. Abilities, items or equipment you can use against any foe in general usually don't count, that is, unless they have a different effect than normal during a boss fight. For example, maybe an item that normally heals the player can be used as a weapon against the boss, or maybe a weapon does increased damage to a certain boss. Keep in mind that regardless of how this trope affects the boss or whether the player chooses to utilize it or not, it must always be possible to win the battle. Also, the effect needs to be intentional by design. No glitches, Game Breakers, or Cheese Strategies are allowed.

Note that, if an action allows you to skip a boss entirely without letting the player fight or interact with the boss, then it's a Skippable Boss. There are a few exceptions to this, though. If you can defeat the boss with a One-Hit Kill (either before or during the fight), end a battle without killing or otherwise harming the boss (there should still be a fight involved), or if fulfilling a certain objective during a boss battle leads to a future boss being skipped, it can still qualify for this trope, so long as the action was done by the player in-game and wasn't done via a cutscene.

Also note that, if an action causes a boss to be replaced by a different boss, then one of two things need to happen for it to still qualify. One, is if it were fought as a pair, group or sequence of bosses, it can replace one or more bosses, but not all of them. Two, is if it either replaces the boss during the fight or is fought immediately before or afterwards. Otherwise, it's merely a Route Boss. A True Final Boss may be eligible for this trope if it meets the above criteria.

Compare Neglected Sidequest Consequence, which covers all negative consequences from ignoring sidequests, including elements outside of boss battles. Contrast Boss-Arena Idiocy and Tactical Suicide Boss where performing a unique action is the only way you can win, and Contractual Boss Immunity, whereas most bosses are usually immune to powerful One-Hit Kill attacks, this particular boss may not be.

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Examples:

Action Games

• Ace Combat X: Skies of Deception has a somewhat open campaign. Which missions you complete, and in which order, decides which of two versions of the game's two boss fights (against the Gleipnir aerial fortress in mission 7 and against Alect Squadron in mission 15) you get as well as the modifiers on those missions (such as limited fuel or enhanced enemy weapons).
  • If you save the Davis Unit (mission 05A Rolling Thunder) then you must complete mission 06B (Ice Bound), which means in turn that you have to face the Gleipnir with its Shock Wave Ballistic Missile (SWBM) launchers intact. If, however, you destroy the Gleipnir's SWBM launchers (mission 06A Midnight Sun) then you must face a much-harder challenge in mission 05B (Pinned down), but the Gleipnir boss fight is easier.
  • If you take mission 13A, Alect Squadron, you can (but don't have to) complete mission 14B, Offline. If you take mission 14A (Fire Storm), you can instead (but again, don't have to) complete mission 13B (Armada). Going for 13A means Alect Squadron's AI in the final battle is worse, but their Fenrirs are equipped with the High-Powered Microwave (HPM) special weapon; completing mission 14B makes the HPM's accuracy worse. If, on the other hand, you go for mission 14A, Alect Squadron's AI is better, but their Fenrirs have no HPM. In this case, completing mission 13B eliminates the naval reinforcements that block your allies' way into Archelon Fortress.
• In Bayonetta, during the cutscene prior to certain bosses, Bayonetta can be seen consuming a lollipop. If you press the right button when you see her put the lollipop in her mouth, it will give her a free lollipop effect at the start of the battle. In Bayonetta 2, if you press the dodge button in the introductory cutscene prior to the boss fight right as the boss attacks you, you will start the battle with an extended Witch Time effect. In Bayonetta 3, you would normally have to defeat Rodin as a Superboss to earn his weapon, but if you die enough times during his fight, he will eventually sell the weapon at his shop for a hefty price.
• Copy Kitty: Boki not taking the offered sword in Arikan battles means battling them without a copied power. Unless the battle has been won below a certain damage threshold, whereupon it can be refought with alternate powers.
• In _iCEY._, there's a boss fight known as Dahal that can be skipped based on the actions taken against the previous boss fight, Trinity. Trinity is a mandatory boss fight, where she will go down after a few hits. After her defeat, she'll be on the ground, where the player can kill her without remorse, or spare her. If the player kills Trinity, then Dahal will fight the player in the following room. If the player chooses to not attack and finish off Trinity while she's down, then the narrator will get annoyed and allows ICEY to go to the next room where the Dahal fight is supposed to take place. However, since the player spared Trinity, who is Dahal's lover, Dahal will keel over in appreciation and lets you go without needing to fight him.
• In The Nightmare Before Christmas: Oogie's Revenge, Jack can put Dr. Finkelstein to sleep for the first half of the battle with a special soup if he collects the ingredients beforehand and brings them to Sally.
• Super Godzilla has a choice in Stage 5 which affects not one, but two bosses:
  • You can go straight for Mecha King Ghidorah. This results in one of the hardest fights in the game due to him having a mountain of hitpoints, and a taser attack which rips off a quarter of your health which he uses if you fail to keep his fighting spirit in check. If you manage to beat him, and the city is at less than 50% destruction, then you unlock the option to turn into Super Godzilla by visiting only one station, then enter Bagan's fight already transformed. The aliens will note the difference, before dismissing it saying it won't matter.
  • You can visit three stations across town to turn into Super Godzilla before fighting Mecha King Ghidorah. This makes the fight significantly easier, since your attacks will deal tons of damage to him while his attacks do barely any - the aforementioned taser attack is the only one which still does appreciable damage, and it's still weaker than your weakest attack. However, this causes the station from the first route to be destroyed (which also happens if the city's destruction reaches 50% regardless of your choice), and forces you to have to hold the line against Bagan as regular Godzilla until the Super X shows up with the energy needed to turn back into Super Godzilla to finish the fight. Until that happens, your attacks will deal Scratch Damage while Bagan will absolutely pulverize you.
• In Teenage Mutant Ninja Turtles: Mutants In Manhattan, if you get good scores from completing missions in a level, there is a chance that a secret boss will appear to help the main boss of the level in the middle of the battle, with the sole exception being General Krang.

Action-Adventure Games

• The Legend of Zelda:
  • The Legend of Zelda: A Link to the Past: Downplayed. The Bug Net can be used to reflect Agahnim's magic bolts back at him. The same thing can be used against Yuga Ganon in the sequel The Legend of Zelda: A Link Between Worlds. It's only slightly more useful than swinging your sword as it covers more range, but it can only be done during these respective boss battles.
  • In The Legend of Zelda: Link's Awakening, a hidden shop that you can bomb open has a Goriya that trades you the Boomerang for one of your other items. This weapon, in addition to collecting items and stunning most enemies, is capable of one-shotting the Final Boss.
  • The Legend of Zelda: Ocarina of Time:
    • The fight with Dark Link can either be one of the easiest or hardest minibosses in the game. He has the same amount of health that you do, which depends on how many Heart Containers you've collected up until this point.
    • If you swing an empty bottle at Ganondorf's magic blasts, it will reflect them. It's only slightly better than swinging a sword as it has a longer animation, but this is notably the only battle this could be done in.
  • The Legend of Zelda: Majora's Mask: After beating the four temples, the player can reach the moon, where the villain Majora's Mask resides. The player has two options: they can either talk to the Majora-wearing boy and face it directly, or they can pass by the four moon challenges and exchange the non-transformation masks with the other four mask-wearing boys. Doing the latter grants the überpowerful Fierce Deity's Mask. With it the player can simply button mash their way to victory, making the Majora battle end in mere seconds.
  • The Legend of Zelda: The Wind Waker: The Forest Haven's Forest Water is meant to be used for the Forest Tree sapling sidequest taking place after you beat Kalle Demos, boss of the Forbidden Woods, but if you bring it to the boss fight, pouring it on Kalle Demos' flower will kill it instantly.
  • The Legend of Zelda: Twilight Princess: The Fishing Rod is normally pointless to use in boss fights. However, if you pull it out in the fight against Ganondorf, he will become so distracted by it that he won't be able to act.
  • The Legend of Zelda: Skyward Sword: The Bug Net is not required to beat Demise but pulling it out during the battle will cause him to temporarily stop attacking, and it can also deflect his Skyward Strike back at him.
  • The Legend of Zelda: Breath of the Wild:
    • You have the option of heading straight to Calamity Ganon after receiving the Paraglider. It's not recommended though, as doing so means that you'll have to fight every Blight Ganon in a row and face a full-health Calamity Ganon. Completing every Divine Beast will eliminate the Blight Ganon boss fights and reduce Calamity Ganon's health down to half.
    • If you drop a Mighty Banana while fighting Monk Maz Koshia, he will become distracted and temporarily stop fighting to eat it. This will only work once per battle, though.
  • The Legend of Zelda: Tears of the Kingdom: If you don't complete the main quests before heading to face Ganondorf, then you will have to fight all the bosses that you would've faced had you completed the quests prior to fighting him, and your allies won't show up to aid you during the final battle.
• Middle-earth: Shadow of War: In order to progress through the game, you have to go through each region and claim the territory controlled by the Overlord Uruks. You must siege the fortresses and eventually walk into the castle and kick the ass of the Overlord in charge. The Overlords aren't stupid enough to go without bodyguards, but you can use that to your advantage. You can take a dominated captain, send them on a quest to become a bodyguard for the Overlord, and when the time comes, they'll betray them and fight on your side instead.
• Ōkami: The Exorcism Slips are typically meant to be used during fights with normal enemies, inflicting powerful damage to finish them off faster. However, if the player brings an Exorcism Slip L with them to the first fight against Orochi, they can use it to instantly end the first phase of the battle after exposing the boss' weak point. However, the trick isn't effective during the second and third fights against Orochi; attempting to use an Exorcism Slip L on him at these points still leaves him with a third of his health.

Beat 'em Up

• Mortal Kombat Mythologies: Sub-Zero: Two instances:
  • If Sub-Zero kills Scorpion with a fatality in the first stage, he will reappear as a mid-stage boss in stage 6, "Prison of Souls".
  • Sub-Zero can use a fatality on Sareena after he defeats her in "Shinnok's Fortress". However, if the player spares her, Sareena will suddenly appear during the Quan Chi boss fight to deliver the final blow, uppercutting the sorcerer out of the arena.

Card Games

• Library of Ruina: The third Keter Abnormality fight with Pinnochio has a sort. Every 3 turns, the main Pinocchio will use a card from a librarians deck that has false information on it. Hitting him with the exclusive "Lying Is Bad!" card when this happens debuffs him, but should it be used early or not used at all, all three Pinocchio's are given 4 more strength and endurance next scene.
• Touhou Lost Branch of Legend: If Megumu is bribed 80 of the unnamed game currency, she'll end the battle 80 Hit Points sooner, and if the Bribery card to do that is recovered via Exile reversal methods, she can be bribed repeatedly.

Fan Games

• Pokémon Reborn:
  • Before your fight against Amaria, she will ask you whether you prefer to fight in single or double battle, affecting both the format of the battle and her team. How exactly it affects the battle varies depending on the route. On the Zekrom route, she will use the chosen format and stick to it if you lose on your first attempt. On the Reshiram route, she will use the opposite format, and it will be randomly chosen for rematches.
  • In the post-game, if you are on Lin route, you get to choose whether the fight against Anomaly Necrozma takes place on a Rainbow Field or a Crystal Cavern.

Fighting Games

• Dragon Ball Z: Budokai Tenkaichi 3's Dragon History single-player campaign has its story events laid out to replicate the original source material as faithfully as it can, with certain events being triggered by button prompts (either allowing a new character to switch in, has the character transforming, etc.). If a player defeats an opponent during a certain phase of the fight or by fulfilling a specific condition, this can sometimes result in a new final opponent of the chapter:
  • During the first battle of the Frieza Saga, "Super Saiyan?!" the player is expected to defeat Recoome, Jeice, and Burter in a row as Goku. If the player lets the fight between Goku and Recoome drag out, eventually a prompt will appear, where pressing it will cause Nail to show up. This will result in a Sequential Boss fight where Nail fights Recoome followed by Jeice, though unlike some of the other optional encounters, Nail's health doesn't recover between the two fights.
  • During the "Cell Games Begin" chapter, if the player loses the prompted fist clash as Goku and gets hit with the following Kamehameha from Cell, when Goku is switched out, Hercule will appear first, allowing the player the chance to win the chapter as him. Downplayed as if the player loses as Hercule, Gohan will be swapped in like nothing happened, only providing an optional dialogue and ending.
  • During the Buu Saga chapter "Destined Battle," Goku fights Majin Vegeta, if no prompts are triggered during the fight and the player beats Majin Vegeta, the Dabura will come out and fight Goku.
  • If Majin Buu is defeated by Majin Vegeta during his playable segment in "Farewell, Proud Warrior" and the player only triggers the first event, Babidi will appear as the final opponent.
  • During "Blaze! Unstoppable Battle", the chapter where Goku fights Legendary Super Saiyan Broly, if the player drags the fight out until Goku's health gets low enough, a button event will appear that switches Goku out for Master Roshi.
  • During the Dragon Ball Saga chapter "Goku Strikes Back!", if the player activates the first prompt and beats Demon King Piccolo without activating the second, Tambourine will be the final opponent of the chapter, and you'll have to fight him as Kid Chi-Chi.
• Super Smash Bros. Brawl: During Petey Piranha's boss battle in the Subspace Emissary campaign, he'll lock Princess Peach and Princess Zelda in two cages. Whichever cage you break first will free that princess and the other princess will be kidnapped. This not only changes the cutscenes but also the playable character that will be paired with Kirby, along with the instigator of a fight between Pit, Mario, Link, and Yoshi later on. Eventually, though, the two princesses will both be saved and made playable.

First-Person Shooter

• Doom 64: The final level has Doomguy fight a massive horde of demons coming from three different gates, and then the Mother Demon who is the Final Boss. However, by unlocking the secret levels from earlier levels and solving certain optional puzzles in them, he'll gather special artifacts which can be used in the final level to shut down the gates and interrupt the horde, which is helpful to save up the ammunition. In addition, the artifacts will also empower one of the weapons (the Unmaker) and give Doomguy the chance to defeat the Mother Demon much more quickly.
• High on Life: If you shoot Douglas before his boss encounter, then he will die upon reaching his suit and you will instead fight his corpse inside his suit. The fight is more or less the same except he doesn't summon any G3 grunts you get some humorous dialogue from Gus.
• Collecting a specific secret item in the first level of SiN (1998) reveals the name of the Final Boss: Thrall Sinclaire, the father of Non-Action Big Bad Elexis Sinclaire. It also unlocks several different cutscenes where the protagonists discuss the events with this newfound knowledge.

Hack-and-Slash Games

• Devil May Cry:
  • In your final battle against him from the first game, Phantom can accidentally kill himself if his "body smash" attack lands several times on the glass floor. This will immediately trigger the cutscene where he's impaled by the knight statue's spear.
  • Devil May Cry 3: Dante's Awakening:
    • If you kill either Agni or Rudra but leave the other one alive for too long, the remaining brother will pick up his dead brother's sword, starts Dual Wielding, and gains access to new, deadlier combos.
    • The Leviathan's Heart fight can become easier or harder depending on which adjacent "lung" should the player focus on (you cannot attack both at once). If you haven't attacked the left lung for a while, it will absorb the Red Orbs dropped by slain Hell Envies. Inversely, the right lung will drain your Devil Trigger gauge if it's left unchecked.
  • Devil May Cry 4: In Mission 18, you can knock The Savior off-balance by striking its head or hands whenever it attacks you in the stage's Floating Platforms. However, the arena has special weapons that optionally make the fight easier, including a cannon that's guaranteed to stagger The Savior.
  • Devil May Cry 5:
    • There's a very brief moment in Mission 6 where the giant demon Gilgamesh runs over some objects in the shipyard and causes several red explosive barrels to roll under its feet. Should Nero shoot these barrels at the opportune time, the explosion is guaranteed to knock Gilgamesh down to the ground, easily exposing its weak spot.
    • A Scripted Event in Mission 14 strips away V's three familiars, forcing you to re-acquire them one-by-one in the upcoming boss fights against the weaker "mirage" versions of Goliath, Artemis, and Cavaliere Angelo. The player can freely determine the order of choosing which familiar to bring, and which boss to fight. If Nightmare returns to V before the player fights Mirage Goliath, V's Finishing Move will be the lengthy cinematic Combination Attack where he impales Goliath's heart. If Nightmare is absent otherwise, V would just perform his most basic finishing move, saving the player several seconds in their mission time.
    • As you explore the stage of Mission 18, you can optionally destroy Qliphoth Blood Clots that are off the required path, causing parts of the last arena to fall off, and reducing Nightmare's chances to heal itself in the middle of the fight.
• Dragon's Dogma: If you give Stefen the real Salomet's Grimoire during a sidequest, he will show up in the "Griffin's Bane" main quest to help you fight the Griffin (by using fire magick, which is the monster's weakness). Should you give him a forgery of the grimoire instead, he will still appear in that quest, but his attempts to help you fight the Griffin with it fall flat when it turns out to be nonfunctional. If the latter consequence happens, he will have a unique dialogue and will become bitter towards the player Arisen.
• Dynasty Warriors and Warriors-style games:
  • There are certain stages with side-missions that you can fulfill to give you advantages against the boss or bosses of that level (raising army morale, weakening the enemy, etc.).
  • Hyrule Warriors:
    • Some map missions have you and the enemy leader attempt to reach a neutral party to try and get them to join their side. Depending on who reaches the neutral force first, you can either get a helpful ally or a powerful adversary.
    • In some of the Twilight Map missions, King Bulbin will appear as a miniboss. You can weaken him by defeating the enemies he summons, but if you instead choose to deplete his health down to 2/3 and avoid killing the enemy soldiers that he summons, he'll instead join your side, impressed by your strength.
  • In Hyrule Warriors: Age of Calamity, the first Guardian you encounter can be beaten either through raw force, or by activating the Guardian statues throughout the level to damage it.
  • Fire Emblem Warriors: Three Hopes changes the behavior of some bosses during the main missions if the player utilizes strategies obtained from side missions:
    • In Scarlet Blaze Chapter 6, you must defeat Lorenz and Count Gloucester to win. Normally, you have to kill or recruit Lorenz first before fighting his father, but if you use the "Build Bridge" strategy, you can take the fight to Count Gloucester first and prevent him from getting a morale boost stemming from his anger at you attacking his son.
    • In Scarlet Blaze Chapter 11, Gustave is one of the primary targets for the mission. If you attack him normally, he'll die and you'll be forced to fight and kill Annette, but if you use the "Backdoor Intel" strategy, you can go around Gustave and attempt to sneak your way to his brother, Baron Dominic. You'll still have to fight Annette, but when you deplete her HP, Gustave will rush to her defense and fight your army in her place, sparing her.
• In the Gauntlet titles Legends and Dark Legacy, there are special artifacts found in each realm which can give players an advantage against each boss. These artifacts will have effects from inflicting a chunk of early damage to temporarily incapacitating the boss.
• In Onimusha 2: Samurai's Destiny, having the closest relationship with Magoichi out of the four allied NPCs will result in him showing up during your final encounter with Recurring Boss Ginghamphatts not long after the fight begins, and then casually blowing Ginghamphatts away, saving you the trouble of a boss battle right before Nobunaga, the Final Boss.

Mecha Games

• Armored Core VI: Fires of Rubicon:
  • During NG, you fight Raven in mission 3-10 "Defend the Old Spaceport". In NG+, if you elected to accept the Rubicon Liberation Front's offer in mission 1-6 "Attack the Dam Complex" and attack your allies G4 Volta and G5 Iguazu, you instead receive "Defend the Dam Complex", where you have to fight two ACs (piloted by King and Charteruse of the Branch hacktivist collective) and Raven — potentially all of them at once if you don't deal with the former quickly enough.
  • During NG++, if you took mission 1-7 "Escort the Weaponized Mining Ship" instead of "Destroy the Weaponized Mining Ship", when you fight Sulla in mission 1-12 "Attack the Watchpoint", he gets a bunch of Ghost mechs as support.
  • During NG++, if you took mission 1-7 "Escort the Weaponized Mining Ship" instead of "Destroy the Weaponized Mining Ship", instead of fighting another AH12 HC Helicopter as the final boss of 3-5 "Survey the Uninhabited Floating City", you fight "Thumb" Dolmayan of the Rubicon Liberation Front.
  • During NG, the midway boss of mission 4-2 "Underground Exploration - Depth 2" is G5 Iguazu. In NG+ it is instead Coldcall, an assassin hired by Iguazu.
  • During NG++, if you've been following ALLMIND's path, then during mission 4-6 "Reach Coral Convergence, instead of having IB-01 CEL-240 as the final boss, you instead fight V.II Snail and G5 Iguazu.
• In an early mission in Mobile Suit Gundam Side Story 0079: Rise From The Ashes Zeon forces have stolen a weapon from the Federation, and you're ordered to intercept them outside of the Zeon-held Alice Springs. Part-way through the battle, however, the enemy commander will offer a cease-fire and withdraw all his forces peacefully. In the final mission, your team will face an enemy Mobile Armor with a massive Beam Cannon mounted on it. But if the player managed to destroy the Zeon cargo train in that earlier mission(by breaking the cease-fire or destroying it before it entered the city beforehand), the armor will be armed with a conventional cannon instead.

Metroidvania

• Bloodstained: Ritual of the Night:
  • The gambling boss Valefar has a move that causes him to absorb all your money to restore its HP once you deplete all of it. The amount of HP restored is determined by how much money you currently have (up to 9999 HP). Of course, if you have no money in your pockets, the boss will exclaim, "What!? You're flat broke!?" and just die instantly.
  • If you defeat Gebel normally, you will get the Bad Ending. However, if you obtained the Zangetsuto from defeating Zangetsu for the second time and use it against the moon in the background when it turns red halfway through the battle instead of defeating Gebel, you'll unlock the path to the True Ending.
• In Bunny Must Die, it's possible to skip the first boss, El Bobomboi, with a precise jump. However, you're eventually required to fight her, as a later event occurs in her boss room. El Bobomboi takes her role as first boss very seriously, and will be absolutely furious that you skipped her, making the fight vastly more difficult.
• Castlevania:
  • Castlevania: Dawn of Sorrow:
    • Dario (2nd round) is the boss in Castle Keep. He can be defeated normally, but this just ends the game at this point. However, the player can defeat a boss named Paranoia in another area of the castle to obtain a soul that allows Soma to enter mirrors. Getting the Paranoia soul and using it during the 2nd Dario boss fight makes the player enter the background mirror and fight the source of Dario's powers, a fire demon named Aguni.
    • The fight with Dmitrii has him copy your attacks by using a Lv. 1 version of your current soul, though he's unable to copy any souls that allow you to shapeshift. Depending on which souls you use during the fight, Dmitrii can either be a Wake-Up Call Boss or a Breather Boss because he'll copy your current soul regardless of how weak it is, which the player can use to either give themselves a challenge or turn Dmitrii into a joke.
  • Castlevania: Portrait of Ruin: After an arduous trek through the Nest of Evil, which involves dealing with an army of Demonic Spiders and bosses from Dawn of Sorrow, you finally come face to face with the Doppelganger. The Doppelganger can copy your attacks and equipment, which would normally make them the hardest fight in the game. The equipment they have however depends on what you had equipped prior to entering their boss room, allowing the player to either increase or decrease the difficulty of the fight depending on their choice of equipment.
  • Castlevania: Symphony of the Night:
    • Depending on how you beat Dracula in the intro with Richter, Alucard's base stats and starting inventory change, with higher overall stats if you take little or no damage and finish the battle quickly, different amounts of starting MP depending on what subweapon Richter was carrying and different consumeable items and minor stat changes depending on whether Richter had no hearts remaining, collected over 40 hearts or got his HP reduced to 0, forcing Maria to assist him by casting a spell to make him invincible for the rest of the fight.
    • You can beat the game if you reach Dracula's Castle Keep and fight its new master, Richter Belmont, netting you one of its endings. However, if Alucard meets Maria in a certain location, he will be given the Holy Glasses, which are useful against Richter, since they reveal a dark green orb floating nearby, which is the real target of this boss battle. Doing so opens up the second half of the game: the Inverted Castle.
• Hollow Knight:
  • At one point, you battle the Watcher Knights, a Wolfpack Boss of six large beetles. Just before the fight, there's a small, well-hidden side path you can take that leads to a chain holding up one of the chandeliers just above their arena. Cut it down, and it will crush one of them, reducing the number of opponents you have to fight by one.
  • Cloth is a recurring character who desires a challenge to test her strength. If you find her in the Ancient Basin, she'll confess her weakness, but continue forward through the inspiration she finds in your courage. From here on, she'll join you in the fight against the Traitor Lord. She'll die at the end, but not before taking the twisted mantis with her. Don't worry though, this is a happy ending, as she's been reunited with her friend Nola in death.
  • Grimm starts his boss fight by bowing to the Knight. If you hit him then, he will screech at the Knight and use his most powerful attack at the start of the fight.
• Iconoclasts: Depending on your Relationship Values with the other characters, the first phase of the final boss changes. If you do everything right, the first shadow becomes less aggressive whereas the second and third shadows will be stunned which is signified by sunflowers particles appearing over their bodies. During the final two phases, Mina will help you fight against the Starworm and later its pilot.
• Iji: On a New Game Plus, you can "maximum charge" General Tor's exoskeleton, giving him the maximum 1200 HP and making his attacks full-strength from the start, as well as spawning skysmashers every attack cycle.
• Metroid:
  • Metroid: Zero Mission: If Samus has acquired 100% of items before fighting Mecha Ridley, its damage output will be doubled, and its total health tripled.
  • Metroid Dread:
    • An example involving Sequence Breaking. If the player manages to find the Morph Ball Bombs before fighting Kraid in Cataris, there's a Morph Ball Launcher hidden in his arena when his second phase starts. If used, it will launch Samus right into his weak point, where players can bomb his belly and defeat Kraid easily, essentially skipping his second phase.
    • Another example involving Kraid, if the player managed to sequence break and obtain Flash Shift early, then go back to fight him, a special animation occurs. If the Flash Shift is used to teleport into Kraid's mouth while his eyes are glowing during the second phase, this allows the player an opportunity to fire missiles directly into the boss' jaw.

MMORPG

• In Final Fantasy XIV, Variant Dungeons are special dungeons where the final boss you face, and certain mechanics are determined based on your choices while exploring. For instance, in the Sil'dihn Subterrane, you'll face Silkie as the final boss of the dungeon if you take the left path, but whether or not it uses its Eastern Ewer attack depends on whether or not the puzzle leading up to it was solved correctly.
• Kingdom of Loathing: The first four undead bosses from the "Undefile the Cyrpt" quest (not including the Bonerdagon) are each associated with a particular item. This item can be found in the same area as the boss and can be used to either do a large chunk of damage to them or score a One-Hit Kill:
  • The giant skeelton is vulnerable to the rusty bonesaw.
  • The Huge ghuol is allergic to the can of Ghoul-B-Gone.
  • The two heads of the conjoined Zmobie can be turned against each other by feeding them a half-rotten brain.
  • The Gargantulihc can be defeated in one moving by finding and breaking its plus-sized phylactery.

Platform Games

• Banjo-Tooie: There are two bosses in Hailfire Peaks, the Elemental Dragons Chilli Billi and Chilly Willy. You have to defeat both of them separately to earn their Jiggy, but the order in which you face them does not matter. There is, however, a perk that affects their difficulty depending on which one you defeat first: By default, both of them have only six hit points; but once you defeat either of them, the other one will have doubled their health to twelve by the time you reach him, thus prolonging his boss fight. This doesn't happen in the Replay Mode, because both of them will have only 6 HP no matter what.
• Donkey Kong Country Returns: Normally, Mugly/Thugly only exposes his weak spot after ramming into a wall or after leaping into the air. However, if you’re playing as Diddy in multiplayer, you can shoot peanuts into his open mouth, distracting him long enough for the other player to stomp on his weak spot.
• Kid Icarus (1986): Freeing the captured warrior angels in the fortress levels will make them appear later to help you fight the fortresses' respective bosses. They're not particularly enduring, however.
• Kirby
  • Kirby Super Star:
    • The game has two battles that can be beaten by picking up some Invincible Candy prior and entering the battle with the invincibility still in effect: Mr. Frosty in Float Islands and Chef Kawasaki in Peanut Plains.
    • The Bonkers battle in Sub-Tree can end just as soon as it starts if you destroy the bridge Bonkers is supposed to land on before he spawns, causing him to fall down the bottomless pit to his doom. If the bridge is destroyed too late, then Bonkers will just leap onto solid ground.
  • Kirby: Triple Deluxe:
    • The fight with Flame Galboros in stage 5 of Wild World can be bypassed in a similar manner to the Bonkers example from Super Star. If you quickly bring a Time Bomb into the fight and destroy the blocks in the centre of the arena with it as it spawns, the boss will hop into the pit, defeating itself in the process. Not as easy to pull off for its DX counterpart in Dededetour!, though...
    • Endless Explosions Stage 1 has some Invincible Candy placed before a battle with Mr. Frosty. Much like in Super Star's Float Islands stage, it's entirely possible to enter battle with the invincibility in effect, taking out Mr. Frosty within seconds.
  • Kirby: Planet Robobot:
    • Much like the Mr. Frosty examples from Super Star and Triple Deluxe, the King Doo battle in Patched Plains stage 4 and the second Security Force battle in Access Ark stage 1 can be effectively skipped by entering battle with the Invincible Candy still in effect.
    • Successfully navigating the Remocodroid in stage 2 of the Access Ark to the end of its section and pressing the background switch quickly will drop the Security Force mid-boss down a bottomless pit before it can even get the chance to attack.
  • Invincible Candy can finish off Wild Edge in the Circuit Speedway stage in Kirby and the Forgotten Land (and must be done to satisfy a certain mission objective for that stage). It can also be done even earlier with the Wild Frosty battle in A Trip to Alivel Mall if the player is super quick.
• Mega Man X:
  • Armored Armadillo will lose his armour if you hit him with his weakness, Electric Spark. This makes him vulnerable all of the time, and completely unable to guard.
  • Magna Centipede loses his abilty to weaken you via magnetizing if hit with his weakness, Silk Shot. He also loses his Magnet Mine attack as well.
• Rainbow Islands: If you collected all nine of the special items in each world, the final boss will become a Zero-Effort Boss that dies in one hit.
• Sonic Superstars: Downplayed. In Cyber Station Zone, there is a boss fight against The Prototype. The Prototype is the robot the player can customize in Battle Mode, with this boss fight always choosing the first of five robots that can be made. While the player can change the boss' look, the customizations do not affect any of its attacks.
• Super Mario Bros. 2: In the Game Boy Advance version, you can remove Birdo's bow by jumping on top of her and yanking it off. You can even return it to her if you throw it back at her.
• Yoshi's Island:
  • Super Mario World 2: Yoshi's Island: If you throw an egg at the Piranha Plant before Kamek transforms it into the Navel Piranha by standing on the very edge of the platform, it will kill it in one hit, and you'll automatically beat the level. This isn't a glitch either, as Kamek will shout, "OH MY!" when he sees you already killed the Piranha Plant and will fly away.
  • Subverted in Yoshi's Woolly World: you can throw a ball of yarn at the Piranha Plant, similar to in Yoshi's Island, but it will only tie it up in yarn and will do nothing to stop Kamek from transforming it into Navel Piranha this time.

Real-Time Strategy

• In the final mission of the Shadow campaign in Age of Empires III: The WarChiefs and Definitive Edition, Chayton Black and the Lakota/Sioux go to war against General Armstrong Custer in the battle of Little Bighorn. The player can let Custer go in with all of his forces, which is a sure way to be defeated, or they can ally with the other Lakota/Sioux tribes and amass a small army in order to destroy as much of Custer's towns and buildings as they can before the attack, in order to reduce the number of forces at Custer's disposal, making the mission way easier.

Roguelikes

• 30XX:
  • If you bring the items for the Imbued Chronovane to Highvault, the level will change so that there is a constant meteor shower in what is heavily implied to be the past. Instead of fighting you, Hoot Omega gains a new Boss Subtitle, "Protector of Elements", and protects you from the meteors as you progress through what would have been the boss arena in a normal run.
  • If you wear the full Vagrant Core set to the Deepverse or otherwise have the set bonus, the level will become corrupted, with swarms of corrupted bits regularly appearing. When you get to the end, Legacy lacks any Boss Subtitles as he becomes a Zero-Effort Boss, doing nothing and dying in one hit.
• The Binding of Isaac:
  • The Bible usually just gives you wings and allows you to fly for one room. However, when used against Mom or Mom's Heart/It Lives, it will kill them instantly. You'll even unlock an item for your troubles! Using it against Satan will kill you instead.
  • Flush! will instantly kill four of the poop-themed bosses in the game. Likewise, Vade Retro will instantly kill all ghost bosses when at or below half of their health. It could even kill Delirium, one of the final bosses, if it transformed into a ghost boss, but this has been patched.
  • Great Gideon is a boss that forces Isaac to fight a six waves of enemies and cannot normally be damaged. Throwing a Chaos Card at it will not only kill it instantly, but open up a unique crawlspace containing two free items and other goods.
  • The Eraser item can erase bosses, so as long as it deals a finishing blow. The boss in question won't appear for the rest of the run, which can help a lot in later floors that are majorly populated by bosses. It also effects one of the true final bosses, Delirium, in that if it tries to transform into an erased boss, it will instantly disappear and spawn the ending chest!
• Dead Estate: Assembling all four parts of the Silver Key by clearing the alternate floors will unlock the coffin on the balcony, which gives the player the Antidote. Bringing this into the boss fight with Chunks on the final floor and injecting him with it will transform him back into a normal rat, ending the fight immediately and unlocking the way into the EXIT Realm.
• DRL:
  • The final boss, the Spider Mastermind, can be nuked if you brought along a Thermonuclear Bomb or some other means to set off a nuke, instantly killing it. Doing so would normally kill you as well, resulting in the "partial win" ending, but if you are also invulnerable when the nuke blows up, you'll survive and instead gain access to one more level, where you'll fight the True Final Boss, John Carmack.
  • If you do the above while also having the Dragonslayer and Berserker Armor equipped, John Carmack will be replaced by the Apostle, an absurdly overpowered Archvile.
• Risk of Rain 2: If the player activates a gold shrine and enters the portal from it, they will enter the Gilded Coast and fight a souped-up Stone Titan named Aurelionite. Your efforts will be rewarded with the Halcyon Seed, an item that normally summons Aurelionite during a teleporter event, but more importantly, if you have it in your inventory when Mithrix steals your items, it will reject him and give you a powerful ally for that phase of the fight.
• Spelunky: Eggplants are seemingly useless items that will break if you don't set them down gently, that is, unless you manage to bring one all the way to the final boss, King Yama. If you throw one at his face, it will transform him into a helpless eggplant monster that can't attack and will die in one hit.

Role-Playing Games

• The original 7th Dragon:
  • An early-game Imperial Dragon, Dead Black/Eclipse, can be weakened by finding an orb key item and placing it on a pedestal in its dungeon: the "incorrect" item, a Big Glass Orb (purchased for a sum of money), weakens it for six turns, while the True Orb (gotten from a quest) does it for ten turns. In its weaker form, the boss has lowered stats and cannot use its signature move that instantly kills any characters with enough HP missing.
  • Imperial Dragon Earthshaker is so massive that it is Mt. Jomaron, the dungeon the party traverses to face it. Going after Earthshaker's head starts the boss fight with it, but it'll have appropriately mountainous health, encouraging the party to traverse the rest of the area and take on each of its body parts in mini-boss battles. Each one defeated cuts off a chunk of its health, so by the time its horn is destroyed it'll be down to two-thirds of its maximum. In addition, it's possible to ask an NPC for assistance in distracting it beforehand, which will occasionally cause Earthshaker to lose its turn.
  • The second and final run-in with Flame Eater sees it residing near a pool of lava, giving it high HP regeneration per turn from the heat. While still killable like this, it becomes easier to fight by traversing its dungeon and killing the two mid-bosses that are supplying that lava, halving and then stopping the regen.
• Baldur's Gate III: During the first encounter with the final boss, there is an "impossible roll" (which requires a 99 or higher on 20-sided die.) Technically a critical hit passes any roll challenge, however if you do this it looks like nothing happens and you still have to run away. After plot happens and you return to face the Final Boss properly; an effect occurs, "Against all odds", which lowers the Final Boss's hp by 10%. You did hurt it after all.
• Bloodborne: One of the first bosses that the player faces in the game is Father Gascoigne, a former hunter who has succumbed to the beast scourge that has ravaged Yharnam. While exploring the city, the player can meet Gascoigne's daughter who will give a small music box. Using the music box during the fight will temporarily stun Gascoigne allowing the player to deal damage to him. Overuse of the music box will cause Father Gascoigne to transform into a beast much earlier in the fight then he would normally, however.
• Bravely Default: The boss fights against Jackal, Erutus Profiteur, and Eloch Quentis Khamer have them all being assisted by Ciggma Khint, who is the more offensive fighter for all three. However, when going through the time loops up until the fifth time, defeating Khint alongside Khamer first will cause both Jackal and Profiteur to be all alone in their respective fights and make them much easier to handle.
• Chantelise: Using the fishing rod "weapon" on the final boss makes the Legendary Shield treasure chest appear, which can be immediately equipped. The Hint for the level gives:
  This time, try humiliating them, utterly.
• Chrono Trigger: Bringing Magus to the boss battle against Queen Zeal will change the battle theme to "Battle With Magus" instead of the default "Boss Battle 2".
• Dark Souls:
  • Dark Souls:
    • The first boss, the Asylum Demon, can be beaten within its first encounter, and you can only win its special weapon if you do so, but if you choose instead to go around it and head to the top of the Undead Asylum, there's a ledge where you can jump down and take off a significant chunk of its health with a plunging attack. If you do not take advantage of this opportunity quickly, though, the Asylum Demon will destroy the platform, bringing you down with it.
    • Downplayed with Great Grey Wolf Sif. In the "Artorias of the Abyss" DLC, the Player Character travels back in time to when Sif's late master Artorias disappeared in the Abyss. Just before the final boss of the DLC, a secret sidepath leads to a cavern where Artorias hid the wounded Sif, and the player has the option of protecting Sif from dark sprites. If they do, Sif will help them fight the final DLC boss and, more pertinently to this trope, recognize the player character in Sif's own boss cutscene (back in the present) and howl in anguish at having to fight them.
  • Dark Souls II:
    • Behind the Pursuer boss is a pair of Ballistas that can be used to take off significant chunks of its health. Be careful, though, as they can also hurt co-op phantoms if they get in the way and the Pursuer can destroy the Ballistas if it gets too close.
    • In Brume Tower, there are four Ashen Idols right outside of the Fume Knight's boss arena. If you don't destroy them using Smelter Wedges before you fight him, they'll heal him during the battle.
    • If you start the Fume Knight's fight wearing Velstadt's Helm, he will automatically transition to his second phase, as its owner is (partially) responsible for having the Fume Knight declared a traitor.
    • The first boss of Frozen Eleum Loyce, Aava, the King's Pet, starts off completely invisible. You are supposed to trek around the level and find the Eye of the Priestess, which lets you see her, but you can fight her without it.
    • There are three frozen Loyce Knights hidden away in various corners of Eleum Loyce. Finding and freeing them secures their help for the fight with the Burnt Ivory King (you get one for free from Alsannah before the fight): the first three knights will each seal a portal that spawns an infinite amount of fairly annoying enemies, while the fourth will continue to fight by your side.
  • Dark Souls III: Yhorm the Giant is weak to the Storm Ruler's special skill "Storm Blade," which you can find by the throne behind him. It's not required to beat him, but it will take you a noticeably longer time to beat him if you don't use it. If you've completed the previous steps of Siegmeyer of Catarina's sidequest, he'll fight Yhorm alongside you with a Storm Ruler of his own.
• In Chapter 1 of Deltarune, the game lets you choose which machine to build in the "Create a Machine to Thrash Your Own Ass" segment. Rouxls Kaard will use this machine against you in Chapter 2 and the head of the machine determines the special attack. The head of the machine also determines the special move that you can use against Giga Queen.
• In Deus Ex: Human Revolution, getting the biochip upgrade before Namir's boss fight will make Jensen vulnerable to Zhao's killswitch, disabling your augmentations and giving you a massive Interface Screw right when you need them the most. Conversely, if you didn't get the upgrade, Jensen will smugly rub it in Zhao's face before facing Namir at normal strength.
• Divinity: Original Sin II:
  • The Demon Lord Adramahlihk is a punishing Optional Boss, but if Lohse is in the party, Malady offers a sidequest to breach his Pocket Dimension and destroy his vast reserve of Soul Power. This reduces his Hit Points and elemental resistances, disables his daemon summons, and prevents him from destroying Lohse's soul.
  • The last quest of the arena chain, "Proving Ground", has you fight a boss battle against the Great Guardian and its flunkies. You can fight him normally, but you can also realign the Eternal Reflectors conveniently located around the arena and power them up with a Phase Capacitor which will stun the Great Guardian and keep its Magic Armor at 0... or you can just pickpocket the Phase Capacitors off it and its flunkies, killing it instantly.
• Dragon Age II:
  • Choosing to be forthright with the Arishok in Hawke's encounters with him, letting Isabela return with the Tome of Koslun, or bringing along Fenris for the ending of Act 2 of the game will allow Hawke to fight him one-on-one as a Duel Boss. Otherwise he's fought alongside several of his soldiers with Hawke fighting alongside their party.
  • In the Mark of the Assassin DLC, Hawke can make a stop in Chateau Haine's kitchen and prepare a meal to be fed to Leopold, Duke Prosper's pet wyvern. When Leopold is fought at the end of the DLC's quest, it will be stunned at the start of the battle if said meal was prepared due to it making the wyvern sick.
• Dragon Quest:
  • Dragon Quest VI: Finding the Super Boss Nokturnus and beating him in less than 20 turns leaves him so impressed with the party's prowess that he grants them a wish. They use that wish to ask him to beat Mortamor the Big Bad for them. Amusingly, this was actually the plan of the king of Graceskull Castle, who unfortunately didn't qualify for the wish.
  • The Tentacular boss in Dragon Quest XI is a notable difficulty spike, unless you explore the town before you fight him and acquire the cannon. This will stun him for a few turns, allowing you to take out his tentacles before he has a chance to attack, tipping the odds significantly in your favor.
• Elden Ring:
  • The first major boss, Margit the Fell Omen, is considered to be a major hurdle to step over. You can technically skip him with an alt path, but there is a way to alleviate some of his difficulty if you wish to progress into Stormveil Castle. Exploring Limgrave, you will eventually find Murkwater Cave, where you'll enter combat with a fellow tarnished named Patches. He'll surrender if you bring him down to half health, at which point he'll become a shopkeeper for you to access. Among his wares is an item called "Margit's Shackle," which you can use against Margit to stun him up twice during his first phase. You can also get the shackle by killing Patches and bringing his Bell Bearing to the Twin Maiden Husks. Margit's Shackle also affects Morgott the Omen King, since Margit is a projection of Morgott's.
  • The Optional Boss Mohg, Lord of Blood has a Shackle that can stun him up to twice during his first phase; you can find it at the bottom of the Subterranean Shunning-Grounds, guarded by two Giant Crayfish. This Shackle also works on Mohg, the Omen, another Optional Boss that bars the way to the Three Fingers in the deepest part of the Shunning-Grounds.
  • There is a Crystal Tear called the Purifying Crystal Tear that is dropped by Eleonora if you defeat her at the Second Church of Marika in the Altus Plateau. Using it during Mohg, the Omen's boss battle will negate the Blood Loss curse that he places on you during the fight, preventing you from taking large amounts of damage.
  • The Mimic Tear is a Mirror Boss that copies your equipment and spells. As such, if you were to enter the arena without any equipment or spells and then reequip them during the fight, it can turn the boss into a Curb-Stomp Battle.
• The Elder Scrolls:
  • Morrowind: Big Bad Final Boss Dagoth Ur has six "Ash Vampire" minions spread throughout his complex within Red Mountain. Killing them before battling Dagoth Ur is supposed to weaken him in various ways (strength penalty, speed penalty, health penalty, etc.), however, due to a limitation of the game's engine, scripts cannot be applied to actors who haven't been loaded yet. To get the penalties, you must first enter the cell containing Dagoth Ur and then go back to kill the Ash Vampires.
  • Oblivion: The final quest in the Arena chain pits you against the Gray Prince, the current grand champion. If you do his personal sidequest first, the fight is much easier, as the Gray Prince refuses to fight at all due to depression from finding out about his half-vampiric heritage.
  • Skyrim: In the Dawnguard DLC, during the final battle with Lord Harkon, you are given the option of handing Auriel's Bow over to him when he demands it. Naturally, he has no intention of actually sparing you, even if you comply, and the battle proceeds as usual, but it becomes more difficult and drawn-out, as the Bow is required to interrupt his healing.
• Epic Battle Fantasy 5 v2 increases HP, Attack, Magic Attack and Accuracy of Final Boss with completion of optional content, namely defeating optional bosses, collecting medals and monster cards. Considering the boss has already ton of HP to begin with it can be rather aggravating.
• Etrian Odyssey IV: Legends of the Titan:
  • The Boiling Lizard, which serves as the boss of the Golden Lair, has an abnormally high amount of HP. While it's possible to defeat it as-is, there's a way to weaken it before initiating the fight: As soon as your character party enters the room, the boss will begin chasing them; while the party dodges it, they can approach the scales that keep the Boss Room hot and use Ice Stakes to destroy them. Once the largest scale is destroyed, the whole room cools down and the HP of the boss is halved, thus giving the party a greater chance to win the battle.
  • The True Final Boss, the Insatiable Pupa, is not only exceptionally powerful but also very durable. If the party characters approach it as soon as they reach the last floor of the Bonus Dungeon, their chances of winning are very low unless they come fully prepared with maximum level, stats and gear. The easier method is to grab a nearby canister and then explore the last floor in its entirety to collect a set of chemicals in a specific order (which can be figured out by collecting a series of posthumous scientific papers which provide specific hints about the chemicals' order of application) and then apply the mix into the Boss Room before entering. Since the characters already have to solve several individual puzzles across the floor to locate the chemicals and then figure out their order of placement (since not doing so will make the compound useless), the whole procedure makes up for a very difficult metapuzzle that requires careful planning, but it's worth it. While the resulting compound doesn't show an immediate effect on the Insatiable Pupa during its larval phase, it does on its Warped Savior form, as it'll have its HP halved and unable to cast its ultimate attack (Ragnarok).
• Etrian Odyssey Nexus: Like in Legends of the Titan, it is possible to halve the HP of the Boiling Lizard before starting its boss fight by heading to the room where the last floor's hot scale is and then destroy it with an Ice Stake. However, due to how far away that room is, it becomes an inconvenience to go back to it in case the party characters die during battle (and thus get a Game Over) or leave the floor before going to the boss, since returning to the floor afterwards will bring back the hot scale.
• In Fallout 4, Mama Murphy has a special power called "the Sight", which lets her see into the future to give you advice, at the cost of requiring her to use chems (drugs), leading to a fatal overdose if you use this too many times. There are a few occasions where using the Sight affects an upcoming boss fight:
  • When rescuing Nick Valentine from Skinny Malone, she'll tell you a cryptic phrase ("remember the quarry and Lilly June on the rocks"). If you repeat it to Skinny in a dialogue option, he'll give you a 10-second chance to leave with Nick peacefully, but if you don't take advantage of this opportunity, he will attack you.
  • Using the sight before the fight with Kellogg, the Starter Villain responsible for your son's abduction, will give you a secret perk that reduces his damage by 25%.
  • When you're going after an Institute Synth Courser in "Hunter/Hunted", Mama Murphy's Sight will have her inform you of a Trigger Phrase you can use against the Synth. If you choose "Reset Code" as a dialogue option when you encounter it, it will force the Synth to shut down. It's worth mentioning that the game effectively treats this as a One-Hit Kill rather than a Skippable Boss since the Synth collapses in-game almost immediately afterwards as if it were killed by the player.
• Fate/EXTRA: Before each Elimination Battle, you're given a week to gather information on your opponent's Servant. Successfully learning more about them (by triggering certain events) increases your Matrix Level on that specific Servant, which then makes the upcoming boss fight easier by pre-emptively revealing some moves in their Tactical Rock–Paper–Scissors queue.
• Fear & Hunger: Termina: Get to the end of the White Bunker on the first day, and unless you're playing as O'saa, August will turn up and shoot the Kaiser in the face with his bow before being struck down. This makes the boss easier by removing his head's resistance to Blindness but will result in the death of the contestant that intervenes to help.
• Final Fantasy:
  • Final Fantasy III: You can choose to fight the Cloud of Darkness after losing the first battle, but doing so would be near impossible as the Cloud of Darkness would have a high defense and a powerful Particle Beam. If the player instead defeats the four Guardians of Darkness, it will free the Warriors of Darkness and weaken the Cloud of Darkness.
  • Final Fantasy IV: Rubicante is a Fire-elemental fiend who absorbs fire attacks. Being a Fair-Play Villain, if you use Fire attacks against him, he will repay the favor by casting Raise on your entire party.
  • Final Fantasy IV: The After Years:
    • If Golbez is in the party when fighting the Four Archfiends, they'll express joy at seeing him again when they're defeated.
    • Bahamut is a boss possessed by the Maenad that will have to be killed unless Rydia has obtained the Asura and Leviathan summons. They will talk Bahamut to his senses, who will then turn on the Maenad controlling him and destroy her with Megaflare, and he will be obtained as a summon.
    • If you don't have Rosa and Ceodore in the party when Cecil and Golbez fight the Dark Knight, then Golbez will sacrifice himself to protect Cecil from a mortal blow from the boss and you'll lose him as a party member.
  • Final Fantasy VI: The Phantom Train can die in one hit by using a Phoenix Down, due to being an undead boss.
  • In the ROM hack Antinomia Final Fantasy VI, suplexing the Phantom Train causes it to be so impressed by Sabin it lets his party leave the train alive, ending the fight in one round.
  • Final Fantasy VII:
    • The final boss Safer-Sephiroth can have his stats increased depending on certain actions taken in the battle beforehand. If you used the Knights of the Round summon on Jenova-Synthesis, killed Bizarro-Sephiroth's head too many times, or have your characters at level 99, then it will greatly raise his maximum HP and stats.
    • Rude, one of the Turks, is secretly fond of Tifa and will refuse to attack her if she is in the party.
    • The Emerald Weapon normally has a 20-minute timer during the fight due to taking place underwater. However, if you obtain the Underwater Materia, that timer will be removed.
  • Final Fantasy VII Remake:
    • Rude will refrain from using most of his attacks against Tifa and Aerith, just as he did in the original version of the game for Tifa (but, there, he would attack Aerith without hesitation).
    • If you use a Fire attack against Abzu, it will set it ablaze and it will jump into the water to quell the flames.
    • The Airbuster can have its move set altered prior to the battle. By gathering key cards scattered throughout the control rooms, you can alter how often the boss uses certain attacks depending on which terminal you use.
  • Final Fantasy VIII: If the player has obtained Odin at Centra Ruins, he will attempt to deliver the first blow to Seifer in his battle at the Lunatic Pandora only for Seifer to slice him in half. If the battle lasts more than twelve turns or Seifer's HP is depleted before then, Gilgamesh will appear to deliver the final blow.
  • Final Fantasy IX:
    • The superboss Ozma normally evades physical attacks and absorbs Shadow-elemental attacks. However, if you encounter all of the Friendly Monsters and give them their requested gems, then Ozma will lose these immunities and become weak to Shadow instead.
    • The boss Valia Pira can have its stats severely weakened if you collect the bloodstones throughout the Desert Palace beforehand.
    • The Soulcage boss, being undead, can be defeated instantaneously with a Phoenix Down, Life spell, or an Elixir. However, using a Fire attack on it will raise its strength, and allow it to use an ability called Fire Blades.
  • Final Fantasy X:
    • Certain boss battles have special actions, called "Trigger Commands," that characters can use to make boss fights easier. For example, in the boss battle against the Oblitzerator, you can cast Thunder on a nearby crane and activate it to heavily damage the Oblitzerator and take away some of its attacks. Certain party members can also talk to two of the bosses: Seymour, and Braska's Final Aeon, raising the party member's stats, or in the case of Braska's Final Aeon, resetting its Overdrive meter up to two times.
    • The battle against the Chocobo Eater can end in three ways: The first way is if it knocks the party off the cliff. The second way is if the party kills the Chocobo Eater normally. The third way is by dealing enough damage to knock the Chocobo Eater on its back and knocking it back until it falls off the cliff. The manner in which you defeat the Chocobo Eater determines what reward you get.
    • Evrae Altana can be fought normally, killed with a Phoenix Down, or you can unlock the gates to escape the battle.
    • If you summon Anima during the final battle against Seymour, he will exclaim, "You would oppose me as well? So be it!"
  • During certain battles in Final Fantasy X-2, you may notice little drone-like enemies called Watchers. If you don't defeat these little guys as soon as possible, then in a later boss fight against the Machina Panzer, the Watchers will disable whatever abilities you used in their presence in previous battles.
  • If you reach 100% Completion before fighting the final boss of Final Fantasy XII: Revenant Wings, then its level will be raised to 99.
  • Final Fantasy XIII-2:
    • Using the Paradox Scope will force you to face harder versions of bosses than you normally would and unlock "Paradox Endings," non-canon alternate endings.
    • Normally, you are supposed to use a device to weaken Atlas before fighting him. However, if you fight him head on, he will be a lot stronger and defeating him in this state will lead to the Paradox ending, "A Giant Mistake."
    • If you fight the Royal Ripeness a second time without resolving the Paradox affecting Sunleth Waterscape, it will have much higher stats than normal and defeating it will lead to the Paradox Ending, "Mog's Marvellous Flan Plan."
  • Lightning Returns: Final Fantasy XIII: Certain bosses can be made harder depending on which day you fight them. Snow Villiers, for example, has two harder forms that appear if you wait too long to fight him.
  • Final Fantasy XV:
    • If you use a Fire spell on the oil barrels near the Deadeye Behemoth, they will explode and cause major damage to it.
    • If you summon Titan during the Adamantoise battle, he will have a unique attack animation where he punches the Adamantoise in the face.
• Golden Sun: The Lost Age: The Serpent is able to recover all of its HP each turn unless you solve the puzzles to expose it to light. And even after you do, he still regenerates quite fast if at least three of the four beams don't reach him. In a New Game Plus, it is possible to exploit game mechanics to defeat the Serpent before his first move (faster than he can regenerate).
• Jimmy and the Pulsating Mass: Johnny Knives' knives can be stolen mid-battle, turning him into the depressed and ineffectual "Johnny No-Knives". When rematched as "Johnny Katana", stealing his katana will make him break down crying and turn him into "Johnny No-Katana", which will make him unable to attack and make all attacks against him 200% stronger.
• Kingdom Hearts:
  • Kingdom Hearts:
    • Prior to the boss fight against the Queen of Hearts and her card soldiers, she will let you gather evidence to prove Alice's innocence. However, being a tyrannical nutcase, the Queen decides to add her own "evidence" and forces you to choose from five boxes at random which evidence she'll accept. The more evidence you gather, the better chance you'll have of getting the right box, but if you choose the box with the fake evidence, then either Donald or Goofy will be blamed for the crime, the Queen will lock one of them in a cage during the battle and you'll have to break them out to free them.
    • If you defeat Lock, Shock, and Barrel in that specific order, you'll receive a higher EXP reward than you normally would if you defeated them in any other order.
    • Unlike other bosses who merely take damage from Fire magic, using it on Captain Hook causes him to take damage in addition to causing his pants to catch fire, causing him to run around the arena and damage Sora on contact.
    • The fight with Ice Titan is the only fight in the game where using Aero magic is outright detrimental. The reason being that your main way of damaging it is to reflect its icicles back at it and Aero magic causes the Titan to summon icicles that are too large to deflect, allowing Ice Titan to effectively counter your use of Aero magic against it.
  • Kingdom Hearts II:
    • If Sora dies during certain boss battles, then King Mickey may appear to save the day, allowing you to play as him temporarily as he fends off the boss and works to revive Sora.
    • Using Magic against Barbossa is more effective than usual as it will temporarily stun him due to being different from the magic in his world.
  • Kingdom Hearts III: Re𝄌Mind: During certain boss battles, you can choose to play as either Sora or one other character, which includes Riku, Aqua, Roxas, and Kairi.
• The Last Story: The penultimate boss fight with Zangurak, the Big Bad of the game, is fought in two phases: one as a Duel Boss with Zael, and the second with the entire party. The second round in particular will give him a shield that can only be broken by his own personal weapon, the Zan Lance, which he will always throw at the player. If the player manages to pick it up before Zangurak can, it can be used to destroy his shield and make it possible for him to be damaged conventionally. However, if the player has Prank Bananas in their inventory, they can fire these banana peels from their crossbow, where Zangurak will comedically slip on them and drop the lance without fail. There are only a few bosses and enemies that are affected by the item, where it can create opportunities to attack. The Prank Banana tactic is viable in both phases of Zangurak's boss fight, where he will be either slipping on the peels to leave him open or won't have a chance to pick up his lance. The Zan Lance in particular can only be obtained if the player deals the final blow to Zangurak in the second phase using his own weapon.
• The Legend of Queen Opala: This RPG Maker H-Game allows you a story option of siding with the good Queen Opala and her mother Farah or betraying them to join the evil sister Osira's quest for conquest. If you side with Queen Opala, the party will eventually find themselves being attacked by a giant kraken at sea. The dialogue allows you to either jump right into combat and fight the squid at full strength, or allow Farah to be violated first, which will exhaust the squid and make it easier to kill. For a woman as experienced as Farah, it's just another day for her.
• Live A Live: The Wild West chapter has you prepare traps to deter O. Dio and his squad of bandits known as the Crazy Bunch, who are coming to raid the local town. Depending on how well you do with the defense, O. Dio will have less minions fighting alongside him, and if you do perfectly, the only threat you will have to fight will be O. Dio himself. If you do not set up any defense, the battle will be stuffed with additional goons to take out, which will greatly increase the challenge, but not make the battle impossible.
• Mario & Luigi:
  • Mario & Luigi: Superstar Saga:
    • During Popple and Bowser's boss fight, if you defeat Popple first, you'll have to continue the fight with Bowser, but if you defeat Bowser first, then Popple will flee the battle to save his own skin.
    • Downplayed with the fight against Jojora. Before the fight, she gives the player the choice of which of her friends she will invite to join her, which may give the impression that the friend you choose will have different stats or abilities, but all this does is change their name. Ultimately played straight, as Jojora will flee if you defeat her friend first, much like Popple.
  • Mario & Luigi: Bowser's Inside Story:
    • The Sea Pipe Statue can normally only be damaged by counterattacks, but if Bowser inhales it, then Mario and Luigi can damage it with their normal attacks.
    • During Midbus's battle, the audience will throw food onto the stage whenever Midbus successfully lands an attack. Midbus will eat the food to heal himself on his next turn, but Bowser can also inhale this food to heal himself instead or give him buffs.
    • If Bowser didn't rescue the Shy Guys from their cage and get their special move, then he won't use their attack when fought by the Mario Bros. as a boss at Toadley's Clinic.
• Marvel Ultimate Alliance: When exploring Mephisto's realm, the player comes across Nightcrawler and Jean Grey, trapped in cages. A Sadistic Choice is given - whichever one the player chooses to free, the other one will be dropped and killed, and the player has to do so in order to continue the game. Later, when fighting Mephisto himself, he will resurrect the mutant that died, and as they're under his control, you'll have to fight them alongside him.
• Mass Effect 2: In Archangel's recruitment mission, the objective is to exfiltrate the mysterious Vigilante Man from being surrounded by an army of mercenaries and gangsters out for revenge. A Renegade interrupt ("You're working too hard") while approaching his hideout allows Commander Shepard to electrocute a mechanic working on a gunship a couple of blocks away. If you take this option, the gunship will be unshielded when it attacks as the mission's boss fight.
• Mother 3: The Steel Mechorilla in Chapter 7 has a big weakness to electricity, but if it gets hit with PK Thunder three times, it'll go haywire and start using a powerful multi-target attack every turn until it dies instead of its normal moves, making the fight much harder if set off too early.
• Neverwinter Nights:
  • The battle with Klauth can be made easier by bringing him an artifact charged with the energy of a dead dragon body, which he will try to consume only to lose a good portion of his health.
  • One of the Words of Power requires defeating a number of ancient golems. They are immune to most forms of damage, but you can do some Retroactive Preparation by traveling to the past and convincing the slaves building them to introduce a weakness to one damage type. Defeating them without doing so is still possible.
• Paper Mario:
  • Paper Mario 64: If you hit the Goomnut tree behind the Goomba King, it will drop a Goomnut that will deal damage to him and instantly take out his minions.
  • Paper Mario: The Thousand-Year Door: The Attack FX R badge changes the sound effect of Mario's jumps and hammer to a cricket sound, which normally doesn't have any practical effect during battle, except against Hooktail. If you attack her with the badge equipped, it will lower her attack and defense as she hates the sound of crickets. The game hints at this by telling you in a letter that Hooktail fears something that starts with "cr" and ends with "ickets."
  • Super Paper Mario: Prior to the final fight against Mimi, she will approach the player disguised as Merlee and ask them which three things they're most afraid of. If you're smart enough to see through Mimi's disguise, you can trick her into giving you helpful items, but if you're being willfully dense, you'll have to fight three different enemies, including Francis.
  • Some of the Thing Stickers in Paper Mario: Sticker Star can have unique effects during boss battles.
    • If you choose to use the Bat during the Tower Power Pokey battle when all five of its body segments appear, it will knock away every one of the segments, leaving the head vulnerable.
    • Any heat-related Things, like a Hairdryer, deal extra damage against the Snow Bowser Statue.
    • If you use a Stapler, Tape, or a Thumbtack during the first phase against Bowser in the Sky Castle, it will seal the doors shut, preventing Bowser from summoning minions.
  • Paper Mario: The Origami King: Scissors starts out his boss fight by putting on his sheathe so that he can have more fun with the fight instead of just killing Mario instantly (given that everyone is made of paper in this game, Scissors' blades can cause a One-Hit Kill if they are touched). The player can decide to either destroy the sheathe or let Scissors keep it on until the 2nd phase. If the player spares the sheathe, then the fight is easier, since it gives the player opportunities to freeze him, thus easier to attack. If the player decides to break Scissors' sheathe, not only will the player be less able to freeze him, but his attacks are also much harder to dodge, as he'll sometimes perform fake-outs, making it harder to predict when he'll actually strike.
• Persona:
  • Persona 5:
    • You can give orders to party members to perform special actions unique to each boss battle. During Kamoshida's battle, you can send someone to steal his crown, significantly weakening him. During Kaneshiro's battle, you can order a party member to throw a rare item to distract him. Most of these are optional, but certain bosses require them to be beaten.
    • In the Royal version of the battle, the cognitive version of Wakaba Ishiki will make disparaging remarks towards Futaba, giving the player two dialogue choices. If you agree with the fake Wakaba, and you would be a major jerk for doing so, then Futaba will be too discouraged to act, delaying the speed at which she summons ballista, and the fake Wakaba will unleash a powerful attack on the party, but if you're protective of Futaba, then she will repel the attack back at the fake Wakaba.
    • If you visit Mementos during Flu Season, there's a chance that the Reaper, normally a powerful Superboss, will be inflicted with Despair, a status effect that will cause it to die in three turns if you encounter it. This only works in the vanilla version, though, as the Reaper will be immune to Despair in the Royal version.
  • Persona 3 Reload:
    • When fighting Jin normally, he'll target the party's elemental weaknesses with his grenades. In the original Persona 3, if the player has a party that had all their weaknesses covered, he'll have a line of dialogue that acknowledges this, but he'll continue fighting normally. In Reload, he will switch up his tactics and start throwing Almighty damage grenades, which can inflict Panic on the party members.
    • Takaya's solo Pre-Final Boss fight in Reload can be affected by the player's choices:
    • If the player meets with Takaya in his final Linked Episode, he tells the Protagonist that he'll be standing guard at the top floor of Tartarus, and gives them one last warning to walk away, which the protagonist will reject. Once the player makes it to his boss fight, he'll refer to his earlier warning, but his boss fight remains the same.
    • During the fight itself, after his health is reduced to 75%, Takaya will ask the player "What is it that you see before you now?" with three different options. If the player answers with the first two, which are more morally-aligned, this triggers an "angry" flag for Takaya, where he uses more instakill attacks and targets weaknesses more often. However, if the player answers with the third option, saying "only the opponent in front of me," Takaya approves of the protagonist for enjoying the moment and the fight in front of them instead, with Takaya's attack patterns becoming more lenient.
• Pokémon games (save for a couple specific examples) start with the player character being given the option between three starter Pokémon. After making your choice, another character always picks one of the remaining options. This can change the team setup of your opponent, and which characters changes depending on the game. It is almost always at least the rival character, but can include others.
  • For Pokémon Red and Blue, the rival, Blue, will always have a team consisting of Pidgeot, Alakazam, and Rhydon for his first three. His last three can possible be some combination of Exeggutor, Gyarados, and Arcanine, with one of them being replaced by his starter. If you chose Squirtle, then he chose Bulbasaur, and instead of Exeggutor, he will have Venusaur. He can also possibly have Blastoise instead of Gyarados, and Charizard instead of Arcanine.
  • For Pokémon Yellow, your character always must obtain Pikachu as a starter. Blue's team changes depending on if you win two optional battles or not. His team has Sandslash, Alakazam, Exeggutor, Ninetales, Magneton, and Cloyster. Ninetales, Magneton, or Cloyster is replaced by Flareon, Jolteon, or Vaporeon respectively based on the previously mentioned battles. Additionally, because Pikachu is an electric type, this means the Vaporeon battle is easier with it being weak to Pikachu, the Flareon battle is indifferent, and the Jolteon battle resists Pikachu's electric attacks.
  • For Pokémon Gold and Silver, the rival, Silver, has a team consisting of Sneasel, Golbat, Magneton, Gengar, and Alakazam. Unlike Blue, Silver's final Pokémon is the only one that changes, being dependent on your starter choice. He can possibly have Typhlosion, Feraligatr, or Meganium.
  • For Pokémon Ruby and Sapphire, The rival character's sex is always opposite the player (Brendan if female, May if male). The team they have is identical either way, but the teammates within are dependent on the starter. Their team consists of Shroomish, Wailmer, and Numel. Like Blue, the starter you pick influences which member of the team is swapped for (Grovyle, Marshstomp, or Combusken). There's also an optional fourth fight where Brendan/May adds a Swellow to their team (the remainder of the team stays the same). The only difference for Pokémon Emerald is their base team (Shroomish, Wailmer, and Numel are switched with Lombre, Pelipper, and Slugma respectively). Their final optional battle will have Tropius as well instead of Swellow, and their Pokémon will be fully evolved except their starter. In the remakes (Omega Ruby and Alpha Sapphire), the rival's gender does actually affect their team: Brendan's Pokémon for some reason have far worse EVs than May's, which translates into worse stats.
  • In Pokémon Colosseum, almost all Pokémon are snagged from other trainers as Shadow Pokémon. Recurring Boss fights, mainly the Cipher admins, will retain their Shadow Pokémon in all later fights with them up to their refightable postgame encounters, but once that Pokémon is snagged, it gets replaced on their team by a different standard Pokémon (example: Miror B. uses a Shadow Sudowoodo for the whole game by default, but if it's snagged during the first fight with him in Pyrite Cave, he'll replace it with a normal Armaldo in Realgam Tower and the Deep Colosseum). The Shadow Pokémon remain the same in later fights because they can't level up, while the replacements get stronger.
  • Pokémon XD: Gale of Darkness doesn't change up recurring opponent teams in the same way as Colosseum, as refought bosses gain new Shadow Pokémon to replace their old ones. Instead, almost all Shadow Pokémon the player fails to snag end up in Miror B.'s collection, and tracking him down in any of his locations will have him use up to two of the missed Shadow Pokémon picked at random so they can be snagged, with the rest of his team being selected from several sets depending on when and where he's fought. The Final Boss still works the original way, however, keeping all six of his Shadow Pokémon in rematches and swapping them out with ordinary ones as they're snagged.
  • For Pokémon Diamond and Pearl, Barry's team can consist of Staraptor, Heracross, Snorlax, Roserade, Floatzel, and Rapidash. He replaces the last three with Torterra, Empoleon, or Infernape (respectively) depending on your starter. In Pokémon Platinum, he keeps the same team minus Snorlax.
  • For Pokémon Black and White, there are two characters who follow this. Cheren and Bianca also pick the remaining starters, with Cheren always picking the favorable choice for him, and Bianca picking the unfavorable one. This time around, two Pokémon for each character change, with Bianca always having a Stoutland and Musharna, and Cheren always having an Unfezant and Liepard. The last two differ heavily, with each having either a Simisage, Simisear, or Simipour (Cheren will always have one that matches your starter's type, while Bianca will always have one that has a type advantage). Besides that, their other Pokémon will be their starter.
  • For Pokémon Black and White 2, Hugh's team can consist of Unfezant, Bouffalant, Elektross, and Flygon. He will also have either Simisage, Simisear, or Simipour (whichever the player's starter has a type advantage over), and Emboar, Samurott, or Serperior (which will have a type advantage over the player's starter).
  • For Pokémon X and Y, Serena/Calem are the rival in the same way Brendan/May are chosen (opposite sex). They will have a team consisting of Meowstic (Male variant for Calem, Female variant for Serena), Altaria, Absol, and one of Eevee's evolutions: Vaporeon, Jolteon, or Flareon. Additionally, their final Pokémon will be their type-advantage starter. There's also Shauna, who will have a team consisting of Delcatty, Goodra, and whichever starter wasn't picked (giving her a type disadvantage against the player starter).
  • For Pokémon Sun and Moon, Hau's team consists of Alolan Raichu, Crabominable, and Komala. He will also have either Leafeon, Flareon, or Vaporeon (whichever has a type advantage against your starter), and his last Pokémon will be the starter with a type disadvantage against your starter. Gladion will also have the same team every time you face him, but his Silvally will always change its type to be an advantage over your starter pokemon. Finally, the champion (Professor Kukui) will have a team consisting of Lycanroc (Day), Alolan Ninetales, Magnezone, Snorlax, and Braviary. His final Pokémon is the remaining starter (which will have a type advantage to yours).
  • For Pokémon Sword and Shield, Hop's team consists of Dubwool, Snorlax, Pinchurchin, and Corviknight. He will also have either Zamazenta or Zacian (which is decided by which version you're playing), and finally either Inteleon, Rillaboom, or Cinderace (which is the type disadvantage to your starter). His older brother, Leon, has a team consisting of Aegislash, Dragapult, Haxorus, and Charizard. One of his other two Pokémon is the remaining starter with a type advantage to yours, and another Pokémon that differs with it. The possibilities are Seismitoad/Cinderace, Mr. Rime/Inteleon, or Rhyperior/Rillaboom.
  • For Pokémon Scarlet and Violet, Nemona will have a team consisting of Lycanroc (Day), Goodra, Dudnsparce, Orthworm, and Pawmot. Her final Pokémon will be the type-disadvantage starter (to yours) she picked at the start. Additionally, Director Clavell will have a team with the first half consisting of Oranguru, Abomasnow, and Polteageist. He can also have Amoongus, Gyrados, and Houndoom. Like Blue, one of the latter three Pokémon is replaced depending on your starter choice (Meowscarada, Quaqaval, or Skeledirge respectively) and thus has a type advantage over your starter.
• Prayer of the Faithless: If the party is in the endings allowing the maximum number of members, the Flunky Boss will give a turn to set up before summoning the flunkies, but not if the maximum member count has been lowered below 3.
• Sacred Earth - Alternative: If Konoe beats the Phantom of the Past, then True Konoe will gain a permanent buff in the final battle. Unfortunately, winning this fight still does nothing to change the Shoot the Shaggy Dog ending.
• SaGa (RPG):
  • SaGa Frontier 2: Once the player makes it to the Star Megalith, they will need to make it The Egg. On the way to destroy it, they will encounter the Anima Lords, optional fights that can be avoided and consist of Water, Fire, Tone, Tree, Beast and Stone Lords. However, defeating each Anima Lord weakens the final boss by removing its associated elemental form and its associated attacks.
  • Romancing SaGa: Minstrel Song allows you to offer up the Fatestones to Saruin, making him more powerful for every Fatestone you've given. Once you've offered all 10 Fatestones to Saruin, he ends up becoming the strongest boss in the game and requires you to pull out all the stops to defeat him.
  • Romancing SaGa 3: Refighting the Sinistrals in the Abyss weakens the Destroyer and prevents it from absorbing their power.
  • SaGa Scarlet Grace: The final boss Firebringer's final form can be upgraded into Firebringer Prime once you obtain all 20 Celesta Quintstones, which requires you to defeat all 20 Scarlet Fiends twice.
• Shin Megami Tensei:
  • In Devil Summoner, the Orgone Ghost in Toa TV Station's radio tower becomes weaker if you defeat its servants, Julia, Speedy, and Mikiya in an optional boss fight in the station proper. The weakened version has lower stats but gains the ability to use Swing Thunder and Rest in addition to its regular skillset.
  • In Giten Megami Tensei, entering Kishimojin Temple during a Full Moon will allow you to meet Hariti, who gives you a bell. Using this bell during a later boss fight with her son, Priyankara will end it early.
  • Shin Megami Tensei V: Ishtar is empowered by 7 Magatsuhi channeling devices spread out across the region of Chiyoda, granting her a total of 8 Press Turns. For each device that is deactivated, her press turns are also reduced which of course means that she'll only have 1 Press Turn if you disable them all. Better still, if you shut off all 7 devices, it also prevents her from using Dreadful Gleam, a powerful Electric skill that pierces Electric resistances and may inflict Seal.
• In Star Ocean: The Second Story, participating in both of the Private Actions involving Philia will remove the limiter on the final boss, making him more difficult.
• In the first Star Wars: Knights of the Old Republic, during the Korriban mission you can poison Uthar Wynn or Yuthura Ban (or both of them), making the two much weaker during the later confrontation with them.
• Super Mario RPG:
  • If you use a Fire attack against Croco, he'll waste a turn trying to put it out.
  • Using Thunderbolt against Mack will stun him for a turn.
  • During the boss fight against Jonathan Jones, if the player takes out all four of his Mooks, he'll challenge Mario to a one-on-one duel, which causes the fight to become a Duel Boss.
  • Exor lacks the Contractual Boss Immunity to the Geno Whirl's One-Hit Kill effect, meaning that after you take out its eyes, and know the timing for Geno Whirl, you can take it out instantly.
• Tales Series:
  • Tales of Symphonia: In the second trip to Welgaia, there are three Optional Bosses representing various motivations of the Big Bad. Defeating them removes specific elemental resistances from the Final Boss.
  • Tales of Vesperia: Witnessing an optional scene between Yuri and Estelle partyway through the game gets you the Mother's Memento item. If you use this during the boss battle with a Brainwashed and Crazy Estelle, it will temporarily stun them. (This is also that fight's Secret Mission) There's also the Fell Arms, optional weapons for each character that get stronger as you defeat enemies. If you collect them all before facing the final boss, he'll absorb their power, preventing you from using them anymore and go One-Winged Angel. Better hope you did this knowingly and are prepared.
• Undertale:
  • Most bosses in general can be killed normally, but the game encourages you try and befriend them by getting to know them and finding out what they like. Each boss is unique in how you accomplish this, and you can go through the entire game without killing a single boss.
  • It's possible to win a boss battle pacifistically and then, when said boss no longer wants to fight, attack them instead of mercy. Not only is this a One-Hit KO but you get unique dialogue from Toriel who is utterly horrified by just how cruel and sadistic you are.
  • If you purchase an item from the Spider Bake Sale in the Ruins, and use it during the fight with Muffet, then she will receive a telegram telling her of your purchase, and she will be pleased by your support, and you can end the fight by sparing her. (If you purchase an item from the bake sale in Hotland, which she runs herself, she won't fight at all, although the prices there are hideously expensive.)
  • When fighting Undyne in the Neutral or Pacifist routes, a couple of the available Acts will affect the speed of her attacks. You can challenge her, which will make her attacks faster, or plead with her, which will slow them down. Both of these will stack, up to a point, if done multiple times.
  • Your decision in rescuing Monster Kid after they slip off of a bridge in Waterfall will affect Undyne's health; should you rescue them, Undyne will have full HP in the boss battle. Should Monster Kid fall, Undyne will rescue them, but at the cost of some of her HP.
  • If you eat the pie that Toriel gave you at the beginning of the game while fighting Asgore, the smell will remind him of her and reduce his stats.
• Yakuza: Like a Dragon: When battling against Kiryu, because of his refusal to hit women, he will not target Saeko and Eri if they're in the party throughout the whole fight. This also applies to his Shadow version in the Final Millennium Tower.
• Weird and Unfortunate Things Are Happening: The hardest-to-reach ending, based on travel time, and its resultant boss, can be seen by getting to the end of Makyo, then turning back just before the last boss of the area and going on the path to the normal end. The normal end boss fight progresses like normal except that there's another phase involving information from the revelations given in the ending from completing Makyo instead.

Run-and-Gun

• Cuphead:
  • When fighting The Root Pack, if you don't shoot Ollie Bulb (the onion), he'll happily leave, and the fight will move on to Chauncey Chantenay (the carrot) early. He'll have more HP than usual, and a radish will pop out of the ground to chase you throughout.
  • If you shrink down while Djimmi the Great reads your mind, he'll create a much smaller puppet than he usually does and advance directly to his final phase, which will have additional HP and the puppet shooting at you throughout.
  • When fighting Sally Stageplay, if you stand on the two cherub cutouts on either side of the stage in Phase 1, the chandelier in the background will fall. If the groom is under it when this happens, it will crush him and end the phase early. This changes the play's story, reskins some of the attacks in the next phase, and adds a second ground-based hazard in the third phase (a cherub rolling a cutout Sun across the stage).
  • When fighting The Howling Aces, if you bring all four of the puppies' HP low without taking any of them out, their mother will round them up and enter a unique final phase where the five of them will attack with homing fire hydrants and pineapple grenades. This phase also lacks the Interface Screw that the regular final phase has.
  • During King Dice's boss fight, he forces you to play a board game before facing him. The number you roll on the die determines which mini-bosses you fight. None of the mini-bosses in of themselves are required to beat King Dice himself, as with good timing, you may be able to skip some of them entirely.

Shoot 'em Up

• Einhänder:
  • Defeating the midboss of Stage 1 by destroying its lower half and traveling through the ruins will give Drache, the end boss of the stage, a different-colored hull. It can also drop a Juno gunpod if certain parts of it are broken off before destroying the boss.
  • Special Bonus Three on Stage 4 will allow you to cause a nuclear meltdown by either destroying a reactor or destroying an enemy that will crash into it. When you Outrun the Fireball, the Sturmvogel boss who shows up to deal with you will have a cosmetically burnt and damaged shell because it was caught in the blast, whereas it will be shiny if you didn't destroy the reactor.
• Star Fox 64: Macbeth has a section that allows you to defeat the boss instantly, by flipping 8 switches at different points on the train rail, and then hitting the main junction switch. Instead of continuing onwards, the track junction diverts the train, causing it to crash into the supply depot and destroy it, accomplishing the mission.
  Train Driver: NO! HIT THE BRAKES! I... CAN'T... STOP IT!!!
  (The train plows into the supply depot tunnel and explodes)
• Touhou Youyoumu ~ Perfect Cherry Blossom: In the Stage 4 boss fight, which one of the three Prismriver sisters you damaged most during the 1st spell card will attack you alone for the 2nd spell card, with each sister having a different attack pattern.

Sports Games

• If you punch out Doc's chocolate bar in Doc Louis's Punch-Out!!, he gets mad and the sparring match gets harder.
  WVBA Message: Removal of Doc Louis's chocolate bar may be hazardous to your health. The WVBA is not responsible for any frustration from this point onward.

Stealth-Based Games

• Metal Gear:
  • Metal Gear Solid 3: Snake Eater:
    • The player can assassinate The End at the earliest opportunity by sniping him at the Ponizovje Docks. Another way you can deal with him is by saving and quitting the game during his boss fight and loading it back up a week later to find that he passed away of old age.
    • In the fight against the Sorrow, he causes the spirits of all the soldiers you killed to appear before you and attack you. Of course, if you never kill any soldiers, then the only spirits that appear are the previous bosses, who die regardless of what you do.
  • Metal Gear Solid V: The Phantom Pain: The water pistol is normally only used as a mere distraction or to short-circuit machines. However, it can also be used to damage the Man on Fire due to being, well, on fire.

Strategy RPG

• Digimon Survive: When players are exploring the old school building after Aoi goes missing, they can find a spirit lamp by finding vinegar to weaken the webs covering the desk it's in. Managing to collect it causes Takuma to toss it at Dokugumon before the actual battle begins and deplete a decent amount of HP.
• Fire Emblem: Path of Radiance: There's a Hopeless Boss Fight with the Raven King Naesala in Chapter 19, but if you have Janaff, Ulki and Reyson with you, one of the former two can speak to him, then he'll talk to Reyson and leave without a fight.
• Fire Emblem: Radiant Dawn: In a case of Dueling Player Characters, Lethe is normally the boss of 3-6. If she died while under your control earlier, another boss named Kezhda will replace her. This character otherwise never appears.
• Fire Emblem: Three Houses:
  • Petra and Bernadetta's Paralogue is available on all routes, but the boss will change depending on your route. It's Catherine for Crimson Flower, and Hubert for all others.
  • During Crimson Flower Chapter 17's battle, Dedue will transform himself into a Giant Demonic Beast after a set number of turns pass, or if the player ends their turn within his attack range. With clever use of movement-boosting skills and Gambits, you can bring a unit close enough to kill him without triggering his transformation.

Survival Horror

• Dead Rising:
  • In Dead Rising, you can participate in a photography challenge with rival photographer Kent. If you can pass his first challenge, he orders you to meet him the next day at noon. Arrive on time, and you'll stop him from zombifying an innocent survivor and fight him with your current arsenal. Arrive too late, however, and Kent will have already zombified the survivor and will tie you down at gunpoint and strip you of your weapons, forcing you to fight him barehanded.
  • In Dead Rising 2, you are pitted against Ted and his pet tiger Snowflake. While you can't do anything to win Ted over, you can tame Snowflake by feeding her steak during the boss fight.
  • Many of the psychopaths in Dead Rising 3 are tied to the Seven Deadly Sins and have a unique weakness that gives you the opportunity to do major damage to them if you choose to exploit them.
    • Albert Contiello, the Psychopath of Greed, is an organ harvester and will become furious if you destroy one of his organ coolers, his one source of income, and becomes vulnerable to being injected with his own syringe, dealing major damage.
    • Harry "Zhi" Wong, the Psychopath of Wrath, is angered by loud noises, and will become momentarily stunned if you hit one of the gongs in his garden.
    • Darlene Fleischermacher, the Psychopath of Gluttony, will be angered if you try to eat some of her food. You can eat this food to restore some health if you run out of food items, but you'll vomit it all back up if you eat too much and don't press the button prompt in time.
    • Kenny Dermot, the Psychopath of Envy, will become jealous if you build a combo weapon, causing him to throw a fit and become vulnerable to attacks.
    • Jherri Gallo, the Psychopath of Pride, will become upset if you counter her grabs, and will go to a mirror and start exercising to rebuild her pride. This leaves her vulnerable to grapple attacks.
    • Dylan Fuentes, the Psychopath of Lust, may request you to pole dance for him. Fulfilling that request will arouse him and leave him exposed to grapple attacks.
• Haunting Ground:
  • Fiona mostly relies on her dog Hewie to do the fighting, but she can also use traps and objects throughout the castle in various ways to slow down or incapacitate her stalkers. However, if Fiona isn't careful, some of the traps can backfire on her.
  • If you can lure Debilitas into the Music Room, you can temporarily incapacitate him by pushing the bookcase on top of him.
  • You can trick Debilitas into falling through a collapsing floor by throwing one of his dolls on top of it. However, if you walk on to the floor, then Fiona will fall through instead.
  • At one point, you can use Hewie to attempt to knock Debilitas off a balcony, but whether Hewie succeeds or not depends on whether or not he is at full health, and if Hewie isn't even close by at the time, then Debilitas will just knock Fiona out.
  • You can order Hewie to hide in a hole and he will attack Debilitas if he comes close by.
  • There are two ways of defeating Debilitas during his final encounter. One is done by using normal attacks, which will kill him, and the other is by bringing down the chandelier on top of him, which won't kill him, but he will cease being a threat to Fiona, leading to getting the best ending.
  • Daniella is normally equipped with a large glass shard, but if you interact with her while she's tending the fireplace, she will replace that glass shard with a hot fire poker, making her stronger and faster.
  • Daniella hates looking at herself in the mirror, and if she comes across one while chasing you, she will be temporarily distracted by it and shatter the mirror.
  • In the Medical Room, there are two jars of acid that can be used against either Daniella or Riccardo: Sulphuric acid and acetic acid. Sulphuric acid will burn them and temporarily incapacitate them, but acetic acid will do nothing.
• Resident Evil:
  • Resident Evil has the option of using V-Jolt against Plant 42. Using it as Jill lets you skip the fight entirely, while using it as Chris significantly weakens it. The same applies in the remake.
  • In Resident Evil 3: Nemesis, if you had Jill jump out of the cable car, then Carlos won't show up before the fight to destroy Nemesis' rocket launcher. If you used the emergency brakes, then he will make an awesome action hero style jump to the rescue to blow it up for good. Doing this also changes Nemesis' model during the fight, leaving him scarred as a result.
  • Resident Evil 4:
    • If you free the dog caught in the bear trap, it will help you in the boss fight with El Gigante. In the second encounter with El Gigante, you can shoot down boulders to significantly damage it. In the third encounter, you can dump one of them in lava using a lever.
    • Though the Verdugo may be That One Boss, it can be made easier if you shoot the liquid nitrogen tanks next to it, freezing it and causing it to take triple damage. For most players who want to upgrade their weapons, this at least gives an incentive to defeat the Verdugo instead of outright escaping, as it drops one of the necessary pieces needed to combine for the most valuable treasure in the entire game.
  • Resident Evil 4 (Remake):
    • Golden Eggs are rare items that are normally used for healing the player. However, if you throw one at Salazar during his boss fight, it will take off 70% of his health due to his egg allergy. This is foreshadowed in a Merchant Request that had you egg Salazar's portrait.
    • During the fight with the two El Gigantes, you can dump one of them into the lava like in the original game, but, additionally, Luis will leave to go fetch some dynamite to help break the armor of the second El Gigante. However, if you already killed the second El Gigante with something powerful like a rocket launcher, then Luis will be left perplexed and disappointed that you didn't leave anything for him to use the dynamite on.
  • In Resident Evil 5, you can kill the Uroboros monster with your guns if you choose to, and you'll win a valuable gold ring that way, but you are encouraged to lure it into the furnace on your first run as your guns are likely not strong enough at that point.
  • Resident Evil 7: Biohazard: During the fight against Jack in the garage, you can hit him with the car if you grab the car keys and turn it on. However, if you're not fast enough, he will instead get into the car and try to hit you with it. Either way, Jack will eventually hijack the car and crash it, setting himself on fire.
• In Rule of Rose, the final boss is Gregory, a man who kills nearly everyone at the orphanage after being driven insane by a jealous Wendy who dresses as his dead son to control him. After you defeat him the first time, a remorseful Wendy will give you a gun to finish Gregory off before being killed by Gregory herself. If you choose to attack Gregory, you will have to fight him for the rest of the battle and you will get the Bad ending. If you instead choose to give Gregory the gun at the start of the battle when he says, "I'm sorry, Joshua," he will come to his senses and, feeling remorse for what he did, will shoot himself and you will get the Good ending.

Third-Person Shooter

• In Kid Icarus: Uprising, the order that you cut off the Hewdraw's heads determines which of the heads you will encounter on the ground level. The fights are all the same, but the dialogue is different.

Wide-Open Sandbox

• Bully: During the boss battle with Johnny Vincent, the leader of the Greasers, he fights you while riding his bike. If you knock out all the Greasers in Pete's way, he'll use the crane's electromagnet to pull Johnny's bike out from under him, forcing him to fight you on foot.

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