History Main / MonsterThreatExpiration

** In the franchise as a whole, many famous kaiju will make reappearances from series to series, particularly if they're well-known in the fandom for being some of the Ultras' toughest enemies. Unfortunately, as a result of becoming recurring foes, they tend to become a lot more beatable (though no less dreaded). A good example of this is Antlar, who could only be killed by the Blue Stone of Barraj[[SpellMyNameWithAnS /Vallarge]] in his original appearance, but is now usually dispatched with a standard Ultraman FinishingMove.

* In ''Series/{{Kikaider}}'', he fights a new MonsterOfTheWeek. Fighting one alone is usually no easy task for him, but in the OVA series, Gill is creating an entire army of duplicated copies of all the robots he ever fought. He managed to kill all of them, with lightening speed. Though this isn't to show the monsters got weaker as much as Jiro became an unstoppable killing machine.

* One of the most jarring cases of this occurs in ''Film/TheLostWorldJurassicPark''. Dinosaurs who are ruthlessly efficient and accurate when taking down most of their victims do mind-bafflingly stupid things when facing the lone woman and little girl in the area such as patiently waiting for the little girl to finish her gymnastics routine which ends with the raptor kicked away somehow, despite how small she is and how little momentum she had accumulated, or fighting amongst each other for the "right"(?) to kill the fleeing woman. The raptors also suffer badly from this in the first ''Film/JurassicPark'' movie as well. By contrast, the Raptors in [[Literature/JurassicPark the novels]] remain dangerous over both books, even when they're not directly threatening the protagonists. The T-Rex actually becomes more dangerous in the second novel, when [[spoiler:our heroes make the mistake of taking a Rex infant. Then they give it back. Then the Rexes try to kill them anyway, because they're in their territory.]]

* In the first ''Film/{{Predator}}'' movie, the eponymous monster systematically hunts down and kills an entire elite special forces unit, only losing due to a conveniently placed trap shortly before it could kill Arnold. In ''Film/{{Predator 2}}'', although it does do quite a number on drug gangs, as soon as Danny Glover manages to track it down (he is a very well-armed cop), he has it on the ropes, lops off one of its arms, and kills it with its own weapon, although it's probably justified as WordOfGod said that the Predator in the sequel was younger than the first, [[SkilledButNaive and obviously less experienced.]] In the original ''Film/AVPAlienVsPredator'', two Predators (out of three) get taken out in five minutes of screentime (although the third one lasts the length of the film). Finally, in ''Film/{{Predators}}'', a trio of stronger, less fettered Predators end up being killed off by a group of similar size to the group in the first film, despite using things such as "hunting hounds" and UAV surveillance, and the fact that while the unit in the first film was a cohesive group (with the exception of Dillon), the group in ''Predators'' was composed of a random assembly of dangerous people who didn't trust one another, including a convict armed only with a shiv. While the final Predator does take quite a lot of damage before succumbing (including being shivved in the neck, fighting a worn-out and injured "Classic" Predator, and having grenades explode in his face), the other two die fairly rapidly.

* The Arachnids in ''Film/StarshipTroopers'' are classic examples of the trope: in the first major battle scene it takes a fire team of soldiers blasting away on full auto to put down one. In the final battle scene, a trio of heroes with the exact same weapons mow them down by the dozens, and other soldiers do so as well. {{Justified}}, as [[AttackItsWeakPoint the Arachnid Warriors can take a lot of damage but go down easily once you hit their nerve stem]]: at the start the still green troopers were just firing at them at random, but later they learned where to hit.

* In ''VisualNovel/FateStayNight'' the anime, Saber and Shirou's battles against Gilgamesh and Berserker

* ''[[VideoGame/DotHackGU .hack//G.U.]]'' has this with Tri-Edge [[spoiler: or rather, Azure Kite]]. He is invincible in the cutscene and effortlessly defeats level 133 "Terror of Death" Haseo, yet by the end of the game, you beat him while you are nowhere near your former glory. Of course, having teammates and healing potions probably helped.
** He averts this in the third volume, when Haseo rematches against him. He doesn't even ''move'' during the fight, just throws powerful blasts of energy at you. Only after you "win" the fight does he prepare to actually get serious and attack directly (by which point Haseo's team is beginning to feel worn out), but [[spoiler:Aura commands Azure Kite to halt his attack and the battle ends there]].

** In ''Tri'' (Wii), as soon as you hit rank 31 and the High Rank quests become available, you start fighting the monsters from the bottom of the pecking order: Great Jaggi, Qurupeco, and Royal Ludroth. Except that in any high-rank quest, there's the possibility that Deviljho will appear, which you're nominally not qualified to fight until rank 51. Thus when you initially encounter Deviljho, you have to run like hell if you want to live, and hope that either Jho or the monster you're tracking retreats from the room, but then you have to take down Jho like any other later on.
** In ''Ultimate'' ([=3DS=] and Wii U), the same thing happens when you start the sixth rank chapter (which corresponds to high rank). One of the first quests requires you to kill 10 Jaggia, but with the twist that Deviljho will lurk around (and it's even introduced in a cutscene where it crushes Great Jaggi from above). And you'll have to avoid it once again during any quest where it might appear, until you're tasked to hunt it in one of the post-finale quests in the ninth rank chapter.

** Taken UpToEleven in the movie ''Film/MegaMonsterBattleUltraGalaxyLegends'', where Belial's Hundred Monster Army includes a number of the Ultras' most infamously formidable foes like Zetton, Tyrant, Fire Golza and Birdon, but every last monster is treated as CannonFodder for the heroes.

** Bakemon grew much weaker over the course of ''Anime/DigimonAdventure''. When they first appeared, it took two Champion-level digimon and some assistance from Jyou to take on a single Bakemon. (Okay, so that was kind of a GiantMook, but the regular-sized Bakemon still were rather competent. They return as part of Phantomon's army in the Myotismon saga, they still require the chanting in order to be weakened, although this could be attributed to power in sheer numbers--''maybe''. But by the time Myotismon is defeated (right before coming back as [=VenomMyotismon=]), they are apparently so weak that the Digidestined's Digimon can each take out multiple Bakemon single-handedly at their rookie stage, though that could be justified with how much stronger they had become by that point.

* In ''Manga/FairyTail'' the first time [[KnightOfCerebus Acnologia]] meets one of the main characters, it's [[TheAce Gildarts]], the strongest wizard in the guild. The Black Dragon takes an arm, a leg, and at least one of his internal organs. When it attacks a group of the guild's elite, Gildarts included, he wonders why they haven't all been killed yet, and decides he’s just playing with them. And it's proven when Acnologia ''stops'' playing and fires an island-destroying BreathWeapon [[spoiler:they all only survive thanks to a special defensive magic spell.]]

* In ''VideoGame/PaperMario'', the recurring enemy Jr. Troopa has reduced HP resulting from having swum to Yoshi's Island and back in pursuit of Mario. This is somewhat mitigated by the addition of a spiked cap. Upon defeat, he then talks as though flight would have made the trip effortless.

* The titular monster in the B-movie ''TheBeing'' has several defense mechanisms, including being able to melt into liquid form and then reform itself. However, it just lets the main character whale on it with an axe at the end without using its powers.

* The eromakadi (eaters of light) from ''The Journeys of the Catechist''. At the beginning they are nigh invincible spirits sucking good things out of the world, the main characters attempt to escape them then barely manage to take out one. In the third book the main character effortlessly dispatches two then weaponizes their bodies.

** {{Justified|Trope}} in ''Film/TheTerminator''; it made sense that the Terminator was getting weaker by the end, due to all the damage it has slowly been accumulating throughout the movie. After it's been run over by a semi-truck, the movie even makes a point of focusing on its damaged-beyond-use leg long enough to let it sink in that, unlike the other injuries it suffered that it was able to shrug off or repair, this one was for keeps. The suspense lay in the fact that the heroes had been getting hurt and killed too.

* In ''Manga/FairyTail'' the first time [[KnightOfCerebus Acnologia]] meets one of the main characters, it's [[TheAce Gildarts]], the strongest wizard in the guild. The Black Dragon takes an arm, a leg, and at least one of his internal organs. When it attacks a group of the guild's elite, Gildarts included, he wonders why they haven't all been killed yet, and decides he’s just playing with them.

* This happened across the board with the ''Franchise/ResidentEvil'' games to the zombies. In [[VideoGame/ResidentEvil the first]] the zombies were quite dangerous, taking as many as 15 to 20 rounds to drop, being difficult to avoid in the narrow hallways of the mansion, and being able to casually drain more than half the player's health from ''a single attack'', meaning the zombies were a genuinely threatening obstacle and not conserving your ammo was basically [[UnwinnableByMistake a guaranteed death]]. In [[VideoGame/ResidentEvil2 the second game]] the zombies went down with less bullets, you had more room to avoid them, you could now ButtonMash to shake them off faster and take much less damage, and ammo was more plentiful, making the zombies less of a threat as you could casually dodge and shoot as you saw fit and still finish the game with ammo in the double digits. The [[VideoGame/ResidentEvil3Nemesis third game]] turned zombies into a near non-threat: in addition to the previous game's changes you now also got ludicrous amounts of ammo to the point you could kill every enemy you encountered and not run out, the quick-dodge mechanic made even using [[EmergencyWeapon the knife]] a viable tactic in battling zombies. It's quite telling how the third game would casually throw gangs of zombies at you for the hell of it which you would take down without issue when in the first game even three zombies in a room would have been an OhCrap moment. Granted this [[Administrivia/TropesAreTools is hardly seen as an issue]] as it paved the way for enemies and boss characters that ''were'' threats, with creatures like the Lickers from the second game and the [[EnsembleDarkHorse much-beloved]] {{Implacable M|an}}en like T-00/Mr. X from the second and The Nemesis from the third who served as the real threats. The ''VideoGame/ResidentEvil'' remake took a "best of both worlds" approach where it gave you more ammo and made the zombies less of a threat, but they would come back as the [[DemonicSpiders much more threatening Crimson Heads]] if you killed one without a headshot or immolating its corpse: headshots were dictated by luck[[note]]shotguns can give an automatic headshot while aiming up, but you need to be practically point blank for it to work.[[/note]] and there was only enough kerosene for 25 zombies on easy/normal and 15 on hard, which wasn't ''nearly'' enough to burn them all, putting you in a MortonsFork situation when it came to shooting or avoiding zombies.

In video games, this may [[DegradedBoss downgrade bosses]] into regular encounters. If the monster's difficulty decreases over a long series, it may be because the characters are [[TookALevelInBadass getting stronger]] and the monster CantCatchUp. In role-playing games, however, this is to be expected because in most cases, your party gets stronger while the enemy monsters don't.

* An inversion of this occurred in ''WesternAnimation/DungeonsAndDragons''. In the first couple of episodes, the band of teenage/preteen adventurers are battling no less than Venger and Tiamat on a regular basis. Midway through the series they're having trouble with orcs and bullywugs. Near the end of the show's run, they had an episode where, in the process of helping some fairy-sized dragons escape to their homeland, they're overpowered and captured by a perfectly normal, two-bit human baron and his dozen or so men at arms....

** Bakemon grew much weaker over the course of ''Anime/DigimonAdventure''. When they first appeared, it took two Champion-level digimon and some assistance from Jyou to take on a single Bakemon. (Okay, so that was kind of a GiantMook, but the regular-sized Bakemon still were rather competent.y return as part of Phantomon's army in the Myotismon saga, they still require the chanting in order to be weakened, although this could be attributed to power in sheer numbers--''maybe''. But by the time Myotismon is defeated (right before coming back as [=VenomMyotismon=]), they are apparently so weak that the Digidestined's Digimon can each take out multiple Bakemon single-handedly at their rookie stage, though that could be justified with how much stronger they had become by that point.

** Also {{inverted|Trope}} with Kefka, who turns from a comic relief pest who's NotWorthKilling when you first meet him, a wuss on the second encounter, a fairly difficult boss battle the third time, to curbstomping the Empire's finest warrior without even caring. And this is all before his ascension to [[AGodAmI godhood]].

** Myotismon suffers one as well in ''Anime/DigimonXrosWarsTheYoungHuntersLeapingThroughTime''. In ''Adventure'', it took seven Ultimates and one Champion to defeat him while a horde of them were defeated by the protagonists Xros Up forms. When they digivolve into [=VenomMyotismon=] and [=MaloMyotismon=], they are easily defeated by the past Digimon Leaders when [=WarGreymon=] and Imperialdramon had difficulty fighting one in their own world.

* '''It takes its time to kill the main characters.''' Non-important characters like police officers are killed in seconds. For the main characters, it just ''stands'' there and roars, or makes threats or evil jokes, and even when it attacks, it tends to miss a lot. JustHitHim!

* In ''Manga/FairyTail'' the first time [[UltimateEvil Acnologia]] meets one of the main characters, it's [[TheAce Gildarts]], the strongest wizard in the guild. The Black Dragon takes an arm, a leg, and at least one of his internal organs. When it attacks a group of the guild's elite, Gildarts included, he wonders why they haven't all been killed yet, and decides he’s just playing with them.

* In ''VisualNovel/FateStayNight'' the anime, Saber and Shirou's battles against Gilgamesh and Berserker -- the two strongest opponents they face in the series are also examples of monster weakening. In the beginning they are no match for their opponents, but in a rematch and after fighting for so long, the enemies attacks seem less effective, and their defenses are penetrated easier. This is especially odd in Gilgamesh's case. Canonically, he is the single most powerful Servant, PERIOD. It's generally agreed that, while not the most powerful character in the {{Franchise/Nasuverse}} (Zelretch and Archetype Earth can probably beat him), against any other Servant there is no reason he should ever lose. The only reason Enuma Elish is survivable at all is because he's deliberately holding back its full strength. The guy is deliberately lowering his own difficulty, mainly due to his ''galactic''-sized ego. If he was a bit less arrogant and a bit more of a CombatPragmatist, he'd wipe the floor with everyone. He only unleashes Ea at full force once: against ''LightNovel/FateZero'' Rider ([[spoiler: Alexander the Great]]). He uses it to destroy Rider's Reality Marble (read: Alternate Dimension). And, as expected, the full power of the sword is so overwhelming that it instantly {{curbstomp|Battle}}s the second strongest servant's ultimate attack.

** Bakemon grew much weaker over the course of ''Anime/DigimonAdventure''. When they first appeared, it took two Champion-level digimon and some assistance from Jyou to take on a single Bakemon. (Okay, so that was kind of a GiantMook, but the regular-sized Bakemon still were rather competent.) When they return as part of Phantomon's army in the Myotismon saga, they still require the chanting in order to be weakened, although this could be attributed to power in sheer numbers--''maybe''. But by the time Myotismon is defeated (right before coming back as [=VenomMyotismon=]), they are apparently so weak that the Digidestined's Digimon can each take out multiple Bakemon single-handedly at their rookie stage.

* In ''Manga/FairyTail'' the first time [[UltimateEvil Acnologia]] meets one of the main characters, it's [[TheAce Gildarts]], the strongest wizard in the guild. The Black Dragon takes an arm, a leg, and at least one of his internal organs. When it attacks a group of the guild's elite, Gildarts included, he wonders why they haven't all been killed yet, and decides it's just playing with them.