Goddamned Boss / Monster Hunter

Just as Monster Hunter has its share of legitimate threats, it also has a few of them that aren't particularly hard, but incredibly annoying and tedious nonetheless. Which, given the fact that there are time limits, is a level of difficulty by itself.

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First to Second Generation (Monster Hunter - Monster Hunter: Freedom Unite)

• If Rathalos isn't That One Boss, he's this due to his tendency to fly around out of the reach of your weapons, wasting your time, while running you over every chance he can get.
• Rathian is significally less difficult to hunt due to staying on the ground more often than her airborne male counterpart Rathalos and her attacks are a bit predictable. That said, you should always watch out for her Signature Move, the tail flip attack, which not only inflicts poison, but also hurts like hell, even if you cut her tail off (though in World and its Iceborne expansion, she won't inflict poison on you if her tail is cut off). Pink Rathian from G is also this due to having the same moves as her regular counterpart, except she's slightly more aggresive. On the other hand, Gold Rathian from that same game is a mix of this and That One Boss for the same reason as Silver Rathalos (stronger than the previous two and having a much thicker hide) and starting from 3 Ultimate onwards, she's much more difficult to be hunted down.
• The -drome series of Bird Wyvern bosses: Velocidrome, Gendrome, Iodrome. In LR, they're only slightly more threatening than a Great Jaggi, but on HR and G/MR, they become exceptionally annoying. They'll constantly use their pounce attack, which will make you miss attacks a lot at best and get knocked everywhere at worst. This is without mentioning Gendrome's paralysis attack and Iodrome's poison breath, both of which are already bad enough on their own. They get worse on multi-level areas, as they'll jump between the two levels in order to make you waste time chasing them around. The narrow structure of these monsters also means it can be hard to land some clean hits on them, especially if they're facing you head-on. Finally, they tend to be encountered with their younger -prey kin, meaning that you'll be constantly dealing with small monsters potentially disrupting your combos or getting in the way of your attacks.
• Bulldrome is fragile as far as boss monsters go and has only a few attacks, two of which involve straightforward charging, but its attacks come out quickly and only one of which (the long charge) is telegraphed, and on higher ranks, it gains a turning charge that can be hard to predict due to its randomized movement, meaning that you can get trampled even if you think you're at a good distance from it. It becomes even more obnoxious when you're trying to fight another monster, as no amount of running away will keep it at a safe distance.
• Plesioth, who is Hitbox Dissonance incarnate and probably the sole reason most hardcore Blademasters would go out of their way to craft Gunner equipment. Seeing it reduced to a fishing minigame in 4U is rather cathartic.
• Before Tri and in 4, there is the Gypceros, a monster encountered fairly early in the game. While it doesn't have much damage potential, it has an annoyingly tough hide for that point of the game, spits poison projectiles, has a flash bomb-like attack that can stun you, can charge in multiple directions without stumbling while spitting poison bombs left and right, and even steal random items that cannot be recovered unlike with Melynxes. It also has a move where it will play dead and attack if you come near, but at least you can carve some materials from it during that move if you're quick enough, and it also serves as an indication that the Gypceros' health is getting lower. Thankfully, in Generations, this is not a smart move for the Gypceros, as it'll just lay there and let you beat the "stuffing" out of it for a bit, provided you don't try to carve it. And of course this is the monster you need to fight for an item that gives you a generous period of unlimited Stamina.
• Gravios isn't called the "Armor Wyvern" for nothing. The first time you hunt it, you'll most likely have green-sharpness weapons at best, and even those will bounce off of any part of its body that isn't its chest. If you're fighting it in multiplayer, you can just assemble a team of Gunners wielding weapons capable of Pierce shots and not worry about sharpness, but if you're hunting it solo, gunner weapons are a highly impractical option due to having less time to shoot safely because of the lack of other players for Gravios to focus on and the relative weakness of your Felyne or Shakalaka companions in tanking Gravios' hits.
• If you plan to take on Khezu or its subspecies, you can forget about bringing Nulberries, because it loves to spam thunder attacks, and if you cure your Thunderblight, chances are the Khezu's just going to inflict it again. Really, the only sure-fire way to deal with its Thunder attacks is to have at least 20 Thunder Res so you can nullify Thunderblight altogether. The Khezu also loves to scale the walls and ceiling, especially in area 7 of the Frozen Seaway, putting itself out of reach of melee weapons. Some of its thunder attacks inflict paralysis, too, leaving you prime for a beating. And like Gypceros, you have to fight this prick ad nauseam to get a decent supply of Mega Demondrugs and Mega Armorskins.
• Yian Garuga was bad enough in the first two games, but its 4 Ultimate/Generations Ultimate incarnation borderlines between this and That One Boss. This is what happens when you take the unpredictable Yian Kut-Ku and put it on monster steroids. It roars constantly, spits fireballs everywhere, has a tail whip that's guaranteed to cause poisoning, can break into a run in an instant, breaks into that run every five seconds (due to the fact that that's how it normally runs), and has pecking attacks that will knock you everywhere, with the "double-beak-slam" variant capable of wiping out a large chunk of your health meter. Said double-beak-slam can have it instantly turn around, it has no windup AT ALL, and is outright spammable while enraged. While this angry Bird Wyvern is not a terribly difficult monster to put down before you and/or your comrades get fainted thrice, it's just a very unpleasant one to fight.
• While Lao-Shan Lung is very slow and nonaggressive, simply walking across the area and ignoring the attacks of hunters until it reaches a barrier or sees them standing on a bridge, it has massive amounts of health, meaning that the fight can drag on for long periods of time if they lack good weapons, and while staggering the beast is all but recommended to keep it from spending too much time in the base point of the Fortress, there is some odd programming that makes it unable to be killed until it reaches it; its health can only go below 50% when it's in the base point (and there is no notable sign of this gimmick taking place anywhere in the battle), meaning that hunters who stagger it too much will find themselves running out of time and repelling the dragon instead of killing it, depriving them of valuable carves. Generations Ultimate seems to have mitigated this problem by reducing the number of areas from four to two and giving Hunters access to the massive-damage Demolisher cannon, although the first area now has a barrier of its own that needs to be defended too. Beyond that, Lao-Shan Lung creates tremors with every step, causing Blademasters to repeatedly have their attacks cut off unless they have Tremor Res.
• Kirin is not a terribly lethal boss, being the least powerful of the Elder Dragons (to the point where prior to Generations it's the only Elder Dragon not to make other monsters bail out of the map), but during its enraged state, only its horn is vulnerable to attacks; everywhere else will just result in bounced hits unless you have Mind's Eye. It is also fast and likes to summon lighting bolts all over the place, making it a literal Lightning Bruiser. World averts this, though...by making Tempered Kirin the hardest monster to hunt in the base game.
• Congalala has a few attacks that cause it to stumble or otherwise lay down on the ground for a few seconds. The catch? Said attacks are certain to knock you down if they connect, and if they don't, Congalala causes tremors when it hits the ground, rendering you immobile and instantly sheathed if the tremors hit and you don't have tremor negation. On top of that, it can eat various mushrooms to gain breath attacks that cause various status ailments, frequently causes the stench status through farts, its stinky breath attack, and flinging shit at you. The Emerald version adds elements of unpredicability where it just does the frog splash move randomly as well as randomly farting when you think there's an opening. Lastly, they're just plain gross to fight.
• Blangonga is a Glass Cannon that's light on the "cannon" and has an average health pool for its place in the hierarchy. However, its habit of jumping around the area, using techniques like tremors, digging, and snowman that waste time more than they hurt, and leaping into the sky to transition to any area it likes make it a pain in the ass to bring down. In short, Blangonga is Rajang Lite.
• Daimyo Hermitaur and Shogun Ceanataur. Both of them move in a manner dissimilar to all other monsters in the game, they are fond of burrowing attacks that are hard to dodge and waste a lot of time, and their claw swipe attack has no tell whatsoever (aside from turning its flank toward you). Shogun Ceanataur in particular has a deceptively long reach with its claws, and Generations makes it worse by granting it access to the Bleeding ailment.

Third Generation (Monster Hunter Tri - Monster Hunter 3 Ultimate/G)

• Any boss in Tri that is capable of going underwater, due to the unpolished underwater controls, assuming they aren't straight up That One Boss.
• Lagombi loves to slip and slide all over the map with little tell, making it feel like a "Get Back Here!" Boss. Some of its attacks can also cause the Snowman status, which not only hampers your movement but renders you unable to use your weapon or use any item besides Cleansers to clean the snow off. If you didn't bring Cleansers, then you'll have to wait for the snow to come off naturally, have an ally (whether another Hunter or one of your CPU-controlled companions) hit you, or get hit with another monster attack...assuming it doesn't knock you into a cart. Not a terribly powerful boss, but you'll probably develop a hatred for rabbits by the time you kill or capture it. Snowman status becomes a non-issue in Rise since snow globs will merely slow your movements now (with Cleansers now only curing Mizutsune's bubbles), but it's still a slide-happy asshole.
• Volvidon, the last member of the Ursid Fanged Beast trio, is a fair annoyance early on in any rank no matter which game it's in. Arzuros is slow with low health and Lagombi only has fast sliding and snowball throws to worry about, but Volvidon edges closer to being a Lightning Bruiser along with having plenty of other tricks. Its gas inflicts Soiled to cut off your ability to heal, its spit can paralyze, and it has a tongue-lash that hits from a good distance away and comes out fast, adding up to lots of weak hits and ailments in addition to the usual heavy attacks. Add in its armored back and tendency to roll around, and Volvidon usually takes longer to beat than it seems like it should.
• The Duramboros is slow as molasses and has predictable attacks, but it's a wall for many inexperienced players due to one major factor: it's one of the biggest non-Elder Dragon Damage Sponge Bosses in the series. Without a good weapon, fighting it can take forever, and suddenly the otherwise long fifty minute time limit becomes a genuine race against time. This is compounded by the fact that the Duramboros, unlike some of the lower level Brute Wyverns, leaves only the briefest of indications where it flees when it digs away. If you can't locate it in a neighboring area, it's plausible that you'll waste even more of your precious time going from area to area searching for it, made especially annoying in the Flooded Forest (the Duramboros' most common level to spawn in) where you have to swim to many areas, that itself is an exercise in patience. On the flip side, traps remove a lot of the frustration in taking it out, poison weapons work wonders against it, and Generations lets you mount the monster to topple it and gain access to its very weak humps.
• Uragaan is basically "Basarios/Gravios as a Brute Wyvern" and hunting it can be very annoying due to its high health, rock-solid back and chin, explosive ores, Sleep/Fireblight-inducing gas, and rolling attacks. It would also slam its chin like a hammer while entering its enraged state. Portable 3rd introduces Steel Uragaan, who is capable of inclicting Soil on you and has a homing rolling attack. Its World incarnation is much worse, since it would usually expel explosive ores before rolling and when you hunt its Master Rank version in Iceborne, it can expel larger explosive ores, which covers a rolling Uragaan with flames on contact.
• Baleful Gigginox ditches its egg-laying ability, freeing you of the worry of Giggis leeching your health away and being inflicted with poison, but in addition to some powerful thunder attacks, it also has a tendency to roar. And basic Earplugs won't protect you; you need high-grade Earplugs to shield against its roars.
• In a weird way, Jhen Mohran and Dah'ren Mohran. If you kill them too fast in the second phase, and you likely will with endgame equipment, their carcasses will be beyond your range of movement and you won't be able to carve them at all.

Fourth Generation (Monster Hunter 4 - Monster Hunter Generations Ultimate)

• Raging Brachydios edges into this. While it is noticeably slower than a regular Brachydios, making its normal attacks easier to deal with, its new slime mechanic is very painful and incredibly annoying. Basically, the slime in its head, arms, and tail is highly volatile and heats up during the fight, exploding when it reaches the limit and (badly) damaging any hunters nearby. The slime goes critical a LOT faster if you are attacking the part in question, meaning you could accidentally nick one of the slimed body parts and suddenly get an explosion to the face and lose close to half of your health. Needless to say, this makes breaking its horn and arms (which you need to do to get its unique parts) a very tedious process. Iceborne averts this, however, and turns it into one of the hardest post-game monsters in the expansion.
• Ash Kecha Wacha moves a lot faster than its basic counterpart, and shields itself with its ears far more often, not only rendering your Sonic Bombs and Flash Bombs moot most of the time, but also bouncing even purple-sharpness weapons off. Imagine the pain of your weapons bouncing off of Apex monsters, but without your Wystones helping you out.
• Malfestio can reverse your controls, which is annoying enough as it is, but can also chain sleep and stun along with it to put you into a Cycle of Hurting. While Confusion isn't too troublesome if you know what buttons to press, there's no tell that determines when it ends, which can disorient players trying to work around it, leading to more dangerous situations. It also likes to fly around a lot and has a questionable hitbox on its glide attack; you'll take full damage from it even if the tips of its wings only slightly grazed you. And if you are the sort that adapts to the reversed controls quickly, and even quickly realize that it ends when two exclamation marks appear above your character, your Palicoes will assume you can't and rush to hit you out of it without fail. This gets really irritating, especially since your character reels pretty far from the hit and takes a second to recover from it, usually right into Malfestio's glide, often resulting in you getting dizzied... which the Palico has significantly less enthusiasm in breaking you out of, of course.
• Deviants:
  • On the Deviant side, most players agree that Dreadking Rathalos is the most problematic of them all. Hits a lot harder than most deviants, requires blue sharpness to cut through nearly everything on it, is highly resistant to element and status on any body part that isn't broken, has absurdly powerful ranged attacks, can inflict severe poison, spends half the fight in the air, and is immune to Flash Bombs while airborne until you wound one of its wings. The Level 10 and G5 Dreadking quests only stockpile the anger by throwing in a Dreadqueen Rathian and a Boltreaver Astalos, respectively, just for good measure. And of course this is the monster you have to fight ad nauseam to level up the Game-Breaker armor.
  • Crystalbeard Uragaan is much like regular Uragaan: huge health pool, tremors upon tremors, poor hitzones, spends much of the fight rolling around, and spams sleep gas in G Rank. Crystalbeard combines this with its chin only being breakable with blunt weapons. This makes its main weak point inaccessible with most weapons and makes its high health feel even higher.
• Any monster for whom breaking and getting parts requires getting a monster to a certain state.
  • Glavenus can go from really difficult, to really tedious if you want to cut off its tail. Unlike most monsters, its tail can only be cut off if it's glowing. Not only is this the point where its tail attacks are at their most dangerous, actually getting to this state can be very time consuming. First, its tail needs to be in its sharp state. Then it needs to perform its Sword Drag move enough times for the tail to become heated. If Glavenus doesn't do it fast enough, its tail will become rusted instead, meaning you'll have to wait for it to start over. If the Random Number God isn't on your side, the game's A.I. Roulette will force you to wait several minutes before its tail becomes hot enough to cut. Once its tail does become heated, you only have a couple minutes before the tail becomes rusted, requiring you to wait through the process again. Fortunately, if you've passed the sever threshold while its tail is cool, a single hit when the tail is hot will pop the sucker right off.
  • Farming feelers from a Gore Magala is much easier if you break them; problem is that this requires getting it to enter its frenzied form so its feelers are up. Unless you save up some weaker weapons, this can be a chore, as you'll often find yourself possibly killing it before it ever gets to that state.
  • Heavy Rustrazor Scalps can only be obtained by breaking Rustrazor Ceanataur's back shell at quests G3 or higher. The Gravios skull has a much higher chance (80%) of dropping the item when broken than the Glavenus skull (55%). However, when Rustrazor Ceanataur changes its shell, the health of the shell resets, and in Gravios mode it moves around constantly, making it very difficult to break the Gravios skull before it switches to the lower-chance Glavenus skull.
• Shagaru Magala is fought in a one-area map where the only way back to camp is through a cart or a Farcaster, is a lot more aggressive than Gore Magala, and the only refuge you have for heals and buffs is a boulder that will collapse if it takes too much damage. All in all, a fight that can get tedious with how little room you have to catch your breath. And if you're playing on a 3DS, especially one of the "classic" (i.e. without the "New" brand) versions of it, there's so much going on that the framerate takes a lot of nasty drops during the fight.

Fifth Generation (Monster Hunter World/Iceborne - Monster Hunter Rise/Sunbreak)

• While Anjanath is the first of That One Bosses in the game due to its attack power and speed, it is ultimately revealed to be this if you have better equipment and you're smart enough to topple it by attacking and breaking its legs, giving you the opportunity to strike while it's defenseless.
• Kushala Daora in World: It loves to spend most of its time in the air, and, when taking off, it creates tornadoes that stun you and take a HUGE amount of space, not to mention they take MINUTES to disperse. If it feels like it, Daora can have three of the damn things out at the same time, making it absolutely impossible to get a hit in and forcing you to just walk away and wait in frustration until the battlefield clears up. Also, halfway through the fight, Daora will form a wind shield around itself that stuns you at melee range and can make certain attacks completely useless. This all adds to possibly the most annoying fight in the game, but Tempered Daora makes it WORSE by eliminating its vulnerability to Flash Pods, taking away the one advantage you have over it when it's in flight. Many players have faced humiliating time over losses when fighting Daora because of all the annoyances. All this adds to Kushala Daora being possibly the most hated of the Elder Dragons. Guys like Nergigante and Lunastra might objectively be more dangerous, but Kushala Daora is simply frustrating and not fun to fight. The icing on the cake? Traditionally Kushala has had a debilitating weakness to poison that rendered it unable to bring its wind barrier to full power and to damage it as time goes on, even in the air. While this vulnerability to poison remains, it does not suppress the wind barrier as this has been relegated to Elderseal. Players are now faced with a choice: Bring a poison weapon to let the status effect chip away at it while it flies at the cost of not being able to suppress the wind barrier, or bring an Elderseal weapon and let the fight drag on as Kushala refuses to come out of the air.
• Paolumu from World: not too tough in and of itself, but when it starts puffing itself up, it can become a serious pain in the ass. Its inhales on the ground can happen at any time, in a split-second, and it staggers your hunter for about five seconds, which Paolumu would capitalize on with charges and tail whacks. Then once it takes to the air, these staggers can go from obnoxious to lethal when a quick, unevadable puff of air can open you up for a butt slam or charge that takes of a huge chunk of health. Not to mention, actually "breaking" the airbag on its neck that it uses to fly doesn't keep the damned thing from filling the airbag with air and just flying anyway. Then Iceborne went and made a subspecies, Nightshade Paolumu, which does all that plus adds a sleep element, with persistent clouds of the stuff and new moves to manipulate them. Better hope you have Energy Drinks or maxed Sleep Resistance beforehand...
• Bazelgeuse, for all of its strength and durability matching its fellow invader and rival Deviljho, is not as difficult as you think. This may be solely contributed to its physical attacks being predictable and a bit slow (even when enraged), but hunting it can be irritating at times due to its explosive scales, which you should always watch out for.
• Vaal Hazak is considered by most to be the easiest elder dragon in World (even its tempered version). However, the fight can still become quite annoying due to the miasma cloud around it that inflicts damage over time, the "undead" Girros that it can summon, and the fact that the fight takes place around pools of acid that deal damage over time. This means that hunts can often end in failure, especially if a player ends up grouped with players who aren't geared properly for the fight. It'll also occasionally move to an area covered with effluvia, which requires a separate armor skill to gain immunity from compared to its own miasma.
  • The Arch Tempered version might actually be That One Boss instead, but for rather infuriating reasons. Someone looked at Vaal Hazak and said "what makes this thing annoying" then cranked all that up to eleven. It always starts in the Effluvia so you're taking Scratch Damage from the start. Its gas armor nullifies shots and arrows everywhere but the head. Its gas clouds do much more damage and it can now stack them several times over. Practically everything it does creates a new cloud. Roar? Creates a cloud. Flinch? Creates a cloud. Even depowering its gas armor creates a new cloud. This means that if you aren't paying attention you can die in literal seconds without it ever even landing a direct hit. Further it absolutely refuses to stay depowered and will spam actions that bring its armor mode back up, which of course results in even more damaging clouds. Then even when it's nearly dead the thing is smart enough to sleep in an acid pool forcing you to take a huge chunk of damage if you want to bomb it and making tactics like the Great Sword's super charge slash impossible to use without someone healing you from the sidelines.
• Lavasioth in World gained a new armor mechanic just like Agnaktor, where its lava shell slowly hardens while it stays out of magma. Unlike Agnaktor, however, its lava shell covers its entire body and cannot be broken, so after enough time has passed, it reduces all attacks to Scratch Damage unless you hit it with torch pods or fire attacks, use Gunlance shelling or blast attacks, or wait for it to return to the magma. Combine this with the ability to spread areas of damaging lava on the ground and an explosive lava ball attack to keep you from being comfortable, and it's not surprising that Lavasioth was the least-hunted monster in the first year.
• The World version of Lunastra is leagues more aggressive than her beau along with sporting higher attack power and HP, with a very nasty trick up her wings in her special flickering blue flames. They do tremendous damage per second that are only partially mitigated with 50 or more Fire Resistance and a Fire Mantle equipped, stick to you and the ground and the kicker? They don't count as a Blight so high Fire Resistance doesn't prevent the damage over time effect at all. And she spreads these EVERYWHERE, it's not uncommon during the course of the fight that the entire area has massive patches of long lasting, high damage per second fiery pain. And then comes her Hellflare attack, which encompasses nearly an ENTIRE zone and getting hit with it is almost certainly a faint since not even the mighty Lance/Gunlance with Guard Up and Guard 5 can block its effects.
  • Lunastra's Hellflare attack deserves special explanation as it's a big part of why she's so difficult. Teostra's fires once for high damage. Lunastra? After the initial extremely powerful blast that can stagger you (even with maxed Windproof), a huge radius around her is covered in fire that's far more damaging over time than normal and will likely eat away what little health you have left. Gaps in the fire mean nothing, the damage will still tick over. Survive that, and she ignites all that fire again for another blast, equally as damaging as the first one, and with no real time to do anything to mitigate it. The spread is so huge that a zone as large as the underground cave in the Wildspire Waste (not Diablos's lair, the actual full-sized cave) will be hit in its entirety. And if you attempt to use a Flash Pod on her while in the fourth stage of her Enhanced Mode, she'll immediately retaliate with Hellflare.
• Ancient Leshen. For starters, it's an event-exclusive monster, so if you start early most players won't be experienced with it and if you start late there's not much time to practice or grind for better gear. While its attacks are just as slow and telegraphed as normal Leshen, it has by far the highest health pool in the game, more than even Extreme Behemoth, ^note It clocks in at 67,500 HP, surpassing Extremoth's 52,500 HP, and even slightly edging out Fatalis' 66,000 single-player health in Iceborne. and its health is always multiplayer-scaled. That health feels even higher with its constant teleporting and barriers. It's surrounded by dozens of Jagras at a time that the Igni Sign can't one-shot unlike with regular Leshen, and they will chip through health like nothing. Its Revolture swarms are further chip damage, with One-Hit KO moves coming later in the fight. It also has a very fast pinning move that it loves to spam and will kill you unless someone else burns the roots or you use a Flash Pod. Ancient Leshen was so obnoxious that it was toned down in an early patch to reduce the frequency of its teleporting and make it more vulnerable to Slinger ammo.
• Shrieking Legiana. It's another persistent flyer that can be tedious to fight for certain weapons, and its wide sweeping attacks will instantly inflict Iceblight on you if your elemental resistance is not up to par(and make trying to Clutch Claw it a good way to get yourself killed). However, what really makes it annoying is that if there is a regular Legiana on the map - and there usually is - it has the ability to call the latter to it's side whenever it wants. You can chase it away with a Dung Pod like everything else, but it's only going to be a matter of time before the Shrieking Legiana summons it again, meaning you're always in danger of getting your combos, stuns, knockdowns, and heals interrupted by an untimely intruder. And because they look so similar, it can be hard to tell which monster is which in the heat of battle.
• Banbaro is one of the first monsters you fight in Iceborne and is as low in the food chain as you can get in Master Rank. It's also an invader, like the viking raiders it resembles, dropping in uninvited in areas totally unfitting for its clearly cold-themed design such as the Rotten Vale and the Elder's Recess and, while it doesn't attack the player on sight, any provocation will cause it to flip out and start charging around the area throwing massive trees and rocks, which can be annoying to dodge if you're already occupied with your actual target.
• Barioth, who is both a Wake-Up Call Boss and That One Boss due to its strength and agility, is also this because while breaking its forelimbs would put a dent in its mobility, the real problem is that cutting and piercing attacks deal less damage on the wings above them. To top it off, the Smithy doesn't have many available pre-MR3 armors with both high defense and Ice resistance.
• Nargacuga is not as difficult as the other veteran monsters from the previous games due to its lack of elemental blights or hard-hitting attacks (save for its potentially fatal tail slam attack, which can be performed up to twice), but it's still agile, smart enough to avoid being pitfalled (unless when enraged), and can shoot spikes that inflict Bleeding. This shouldn't go without mentioning that it has 1000 more health than Barioth and Tigrex.
• Acidic Glavenus is either this or That One Boss for a couple of reasons: Much like Fulgur Anjanath, it lacks any fire attacks but its throat doesn't glow after sharpening its tail, moves faster than its regular counterpart, and is now capable of inflicting Defense Down on you by utilizing corrisive attacks. To make things even worse, you'll have to hunt Acidic Glavenus at the Rotten Vale and the Rotted region of the Guiding Lands.
• Gold Rathian and Silver Rathalos have a special feature unique to them in Iceborne: They won't leave their starting area. Because of this, they'll keep on attacking you until either they're hunted or you're out of their sight. This means there are no breathers during the fight to recover or set up traps unless you distract them with a Flash Pod. On top of this, they also have a Super Mode and extremely powerful attacks capable of almost finishing you off in one shot, inflicting both Severe Fireblight and Poison (or Noxious Poison in Gold Rathian's case) regularly, and leaving large fire patches that can chip off your health. And the worst part is where you're hunting them in Quests: Area 15 of Elder's Recess (Nergigante's lair), a place where there's no slinger ammo for toppling through wall slams (though Slinger Capacity comes in handy for this), very few spots for sliding attacks, and only one small ledge for mounts or jump attacks; hardly an ideal place to spend twenty minutes duking it out. And then there's an Optional Hunting Quest where you'll have to hunt both of them in the same area of that locale. Thankfully, only Gold Rathian is present at the start of that Quest but it won't help you that much because if you're not finished hunting her within ten minutes before Silver Rathalos shows up, they'll waste no time ganging up on you.
• Slaying Ruiner Nergigante is much less difficult than the original Nergigante and its Arch-Tempered version, even more so with endgame MR equipment. However, while it lacks the infamous divebomb attack, it's still as aggressive as ever, it can perform sliding charges across the area without warning, and its ironspikes can even make you bleed, meaning that carrying Astera Jerkies or having maxed Bleeding Resistance is needed to mitigate this problem. Plus, its body parts are rock-solid all over due to its ironspikes, so you'll have to constantly tenderize them with the Clutch Claw or have Mind's Eye to keep your weapon from bouncing off, especially if you're trying to cut off its tail. Also, an Event Quest where you're fighting a Tempered one (who has Arch-Tempered Nergigante's leaping slam attack) is one of the most efficient ways to get Great Spiritvein Gems, which are needed for almost every augment, so have fun with that.
• Alatreon is both this and That One Boss due to its mechanics. It releases a One-Hit Kill move known as Escaton Judgement if you don't deal enough elemental damage to it before a certain period of time passes, which changes its elemental weaknesses if you haven't broken the horns. This is easier said than done, since Alatreon is really nimble and barely gives you any room to breathe, plus it spends a significant amount of time flying, crimping your elemental DPS as you can only hit it with the Clutch Claw. Fortunately, the horns just snap off like twigs if you can land a few good hits on them in Dragon Active and since its an Optional Boss, unless you want to unlock Fatalis by completing the second Alatreon Special Assignment, you don't need to slay it.
• Almudron in Rise at first glance seems to be a very cool boss fight... until you realize he is so huge that he eats the entire camera if you are up close, meaning it is impossible to see half of his move tells until you've already lost half of your health. He moves around constantly and loves to play keep away when in the mud, and his claws make green sharpness bounce. Combine this with the mud waves he throws around, acidic mud that both slows you down and quickly gnaws at your health, and the constant burrowing and leaping making it nigh-impossible to land a hit on the damned thing when it's in the mud, and you have a recipe for an incredibly annoying fight. To say nothing of the mud ball he can create and then slam down at a moment's notice, which hits like a nuclear warhead with the range of one too, and a tell that is nearly impossible to tell from his normal tail swing with the mud ball... To make matters worse, its Golden Almudron Orbs have a 1% drop rate (on par with Rathalos, Rathian, and Magnamalo) in target reward tables than most rare drops (Though this was eventually made less of an issue in Sunbreak due to the fact that they drop more frequently in Master Rank, as well as the fact you can eventually just buy them from Bahari if you grind up Anomaly Coins.)
• Jyuratodus was a pushover back in World due to its mud armor can be easily removed by Watermoss shots (even in HR and MR), but definitely NOT in Rise: It's slightly more agile, its roar can flinch you like Beotodus from Iceborne, has a much stronger hip check attack (albeit not as strong as Plesioth's), and due to not having Watermoss in the latter game, you'll have to get rid of it's mud armor the old fashioned way. And the worst part is, Jyuratodus is a HR5 Monster when you attempt to hunt it the first time, which is a huge step-up compared to its World counterpart, who is first hunted as a LR3 monster.
• While Apex Diablos is a That One Boss due to having borrowing some of Bloodbath Diablos' moves as well as its main gimmick, it's actually this in Rampage and goes down fairly quickly if you know exactly what you're doing. Yes, it is a heavy hitter (and its damage output is just as obscene as a Deviant or a Tempered Monster to boot), but it has fewer attacks than when you fought it in its Hunting Quest, and its main priority is just attacking defenses (Hunting Installations or otherwise) as well as the main gate.
• Basarios in Rise is just as annoying as its previous incarnations due its really thick hide and it's even more so when you hunt its MR version in Sunbreak: it can do a double roll not just as a standard attack, but as a combo out of every other move it has. It charges at you? Enjoy a tracking double roll that will chunk your health that early on. Heat beam? Have some more rolls to waste your time and body you with. Be ready to watch your healing item supply dwindle with every double roll Basarios does unless you know to expect it or get lucky with avoiding it.