Note that some of these bosses end up being normal mid-bosses in later events, and depending on the era and/or current power curve of a majority of the characters in that said era, these specific bosses might be a mere nuisance (or some of them might return to be even more powerful than before). Basically, these Superbosses are always going to be this unless you've absolutely maxed out weapons via limit breaking them, which isn't as easy to do since you have to rely on stacking/grinding Power Stones and/or getting the right weapon drops for the right characters needed.
- The Lost Chapter's Hard Mode Bosses are absolutely ruthless, being overpowered, overleveled, and during the final mission are fought as a Dual Boss. While some are easy depending on the current power level of the character roster within the era, others are quite infamous even to this day.
- Early on before awakenings were a thing, one of the most difficult offenders is the boss for Vanille's Lost Chapter, the Berserker Armor. Based on the Iron Giant-type of enemy, Berserker Armors have high defenses, resist every attack except magical-based ones, hit like a freight train, and can buff itself with Haste or Berserk status letting it hit even harder and faster without being able to predict its target(s). The only party members that can do good damage to them are mage-types, however the issue there is so many magical-type characters are of the Squishy Wizard variety that although they'll have the offense to make a dent in the Armors, they don't have the survivability to not get KOed, on top of the synergy for the event being all support-type characters (Vanille, Hope and Yuna). Also, as mentioned above, the last battle of the Lost Chapter has you fighting two of them at once!
- Faris' event/Lost Chapter boss, the Lamia Queen, was always paired with two Manikins she will focus on reviving if any one of them die. On top of that, she has a Magical Allure attack that will both sap and skip the target's turn (even if they're a female unlike with normal Lamias), and on Hard Mode, she's paired with a Ramza and Shantotto manikin, meaning buffs on top of debuffs. Pray to god RNG is on your side, otherwise the Queen will make things miserable for you.
- The Raging Tortoise from Ace's release event Unparalleled Power is generally disliked among the character event bosses as it spends around 90% of the fight inside its shell, turning it into a Stone Wall Damage-Sponge Boss. This causes fighting it to be a grind that takes longer than other bosses, whom can usually be defeated pretty reliably with a Chocobo/Sylph x3 Zerg Rush from a competently leveled party of damage dealers (hence there's a reason why Bartz was synergy due to his Missile's percentage damage and Vivi's fire as the bosses are weak to that element). Even worse is when it can choose to raise its BRV then instantly decide to one-shot HP Attack you out of pure chance afterwards if it steals your turn (if your character/team comp is too slow), which is something proven in the Global 6th Awakening Batch Heretic quests and the co-op when a stronger version of the turtle made a return. For the Lost Chapter version, it also introduced the need to have the star character in your party for the boss nodes to get the 3rd gem mission reward, making it hell if you have not-as-decked-out Ace that needs to be carried just for those rewards.
- A good number of the red-colored node bosses in Hard Mode tend to really take the cake, especially if they gain some extra properties that will make them even more difficult to deal with compared to Normal Mode. Examples include nearly any form of Malboro on that node ending up with new resistances compared to their Normal Mode versions, such as suddenly being resistant to either physical or magic attacks.
- Lenna's event/Lost Chapter involved the Savage Drake, which had plenty of debuffs added with poison (essentially, a Malboro on crack with the power of Dragon-type monsters). If you don't have any way to shove off, cleanse or protect against the debuffs, you're going to have a very hard time. The Global version of the EX stage with this boss especially was considered to be far too hard for anyone who didn't have the best units pulled for (which were Lenna and King, despite Sazh's early 35CP weapon).
- Deuce's event involved a pair of unique Krakens known as the Count Steams that all happen to be resistant against melee attacks, or anything physical (thus magic DPS units have to be used against them due to their weakness to magic). But not only that, they had their unique invisible "gathering steam" buffs which increased both the krakens' speed and attack, allowing them to turn into Lightning Bruisers that could nuke your party if you failed to keep them under control as their invisible buffs could not be dispelled normally (nor could you debuff them with a speed down). It was met with some notable complaints back then on the JP forums due to such difficultynote . Even worse, you had to kill them at the same time, otherwise the one remaining alive would enrage themselves and dispel their current debuffs. The Chaos difficulty version of this fight in her Lost Chapter is even more annoying, not only because of increased stats, but also because one of the missions requires you to beat the fight with 0 HP damage taken, which is unreasonable at very least.
- Agrias' event boss, the pair of Argent Officiants, were quite the chore due to similar issues like with Deuce event bosses, though at least you can make use of a dispeller....if they are fast enough (as this is where Faris' issues with turn rate increase come in, despite her high base 5/5 speed and her being synergy in the event). They also dispel their own debuffs as well, meaning you have to keep reapplying them (especially if you use someone like Layle for his Force debuff).
- Eald'narche when he is fought in Arc 2 Chapter 6 is yet another villain who's paired with Manikins; however, the ones he's paired with are a Ramza and Warrior of Light Manikin. The biggest problem here is that Eald'narche has a non-framed debuff called "Drowsy" induced by his Sleepga II attack (a very potent Attack and Speed Down debuff rolled into one). And if you bother to kill the Ramza Manikin, a Lenna Manikin will be summoned in its place to provide Initial BRV down debuffs, heal Eald'narche and shield him from debuffs.
- The Lufenia difficulty boss fight of Arciela's Lost Chapter is notorious for being one of the single worst fights in the entire game. The condition to increase the orb is to dispel the boss's buffs. Seems simple enough, after all, the boss can buff themselves on a regular basis, right? Yeah, no. There is a good chance that the boss's attacks won't give them a buff at all, which means there's nothing to dispel. So not only do you have to deal with the intense difficulty that is Lufenia, whether you get to increase the countdown orb is PURELY RNG-BASED. This means you can get totally unlucky and have the boss just not buff themselves, which means your party is DOOMED and there's nothing you can do to stop it.
- Both Lufenia fights against Divine Shiva are generally agreed to be one of the most tedious and annoying fights of that difficulty: like the previous fights against her, her Diamond Dust freezes your characters, forcing them to waste their next turn until she gets another turn and it also disables any counterattacks, which can easily cause you to fail the turn limit requirement, and on top of that, she also has the normal Lufenia orb attack, which, while not particularily dangerous due to the fact that it's not a Total Party Kill, will still execute instantly regardless of turn order and is nearly impossible to manage with a team that can kill her within the turn limit without a party fire enchant and traps that can still deal damage while you're frozen, and she also executes the aforementioned Diamond Dust once her HP hits specific thresholds, as well as gaining a 1 million HP damage shield whenever she breaks someone, which she'll get automatically from Diamond Dust since it instantly breaks you. As an additional "fuck you", she also reflects all turn delay and deletion effects back to their source, has an innate 150% launch HP damage reduction which makes Raines useless and Diamond Dust also has another effect that makes her absorb all elemental damage except fire for 3 turns. So in summary: you'll spend most of the battle watching Shiva take a seemingly endless number of turns while you sit there helpless with your buff durations running down, when you get an opportunity to deal good damage, chances are the first million HP of it will be nullified, and most of the methods to deal tons of damage to her quickly or prevent her from taking turns are countered by her mechanics.
- Tier 6's Reckoning of Dimension's End: Transcendence has the unbelievably obnoxious Purpure Mantis as the second wave's boss. To compensate for their lack of a special countdown and the fact that they only have a single basic HP attack that they rarely use, they instead sport extremely irritating mechanics that must be controlled by inflicting debuffs on them. If they have no debuffs, you straight up cannot damage them. If they have less than 6 debuffs, they instantly take their turn and smack your party around every time a party member takes any action. And you have to learn to manage your debuffs, because they fucking cleanse all of their debuffs at 89% and 59% HP, forcing you to go through their annoying gimmicks again until you can debuff them enough. Tier 6 is widely considered to be one of the worst Transcendence stages to be released, and for very good reason.
- Tier 10's Reckoning of Dimension's End: Transcendence is notorious for being completely impossible to clear if you lack an FR weapon. This is because at 40%, the boss regenerates 1.1 MILLION HP for every action your party takes, which leads to utter madness if you don't utilize the Force Time mechanic to seriously jack up your damage to rush through the pesky regen. For reference, every other Shinryu difficulty stage has been able to be cleared even without utilizing Force Time to some extent. And what's more, not only does the fight share Tier 6's debuff mechanic, but it also has another earlier tier's gimmick in form of summoned enemies that need to be reduced to 50% or less HP by the time the boss hits specific HP thresholds: once it does, it'll command the other enemies to attack your party, which will be an One-Hit Kill to the targetted party member if the enemy's HP is above 50% HP.
- The Pandemonium Spiritus fight against Ancient Guard is a colossal pain in the ass to beat due to massive HP damage reductions present in the fight as well as many contradictory mechanics you need to put up with, alternately forcing you to prevent it from getting any turns and letting it have a turn: once you reduce its HP to 89%, you need to reduce its HP below 79% without it getting a turn or it heals back 10% of its HP and removes all its debuffs, and from 59% onwards, it becomes immune to all BRV and HP damage until it gets a turn after 10 player turns outside of burst or summon and reduces all HP damage done outside of launches until its Mooks are defeated. The last 19% of its HP are the worst, as it becomes essentially immune to all HP damage outside of launches, and it'll spam Forest Press+ every turn for the rest of the battle, which not only ignores HP and BRV damage mitigation, but also inflicts 2 turns of Paralyze on everyone, essentially stunlocking you to death if you let it have a turn without some form of debuff immunity or a way for the entire party to evade its attacks, and since you still need to let it have a turn for every 10 player turns, the last part of the fight is essentially on a strict time limit. Its Mooks aren't a joke either, as their only attack likewise ignores BRV and HP damage mitigation and delays the target. Finally, since it's a Spiritus fight, there are rewards for beating it with only characters from specific realms, with specific crystal colors and using specific weapon types, and since it heavily resists all non-magical damage, this greatly narrows down potential options.
- Bhunivelze, the Act 3, Chapter 10 Part 2 final boss is brutal in Shinryu difficulty. It is immune to break, delay, and turn deletion, it has ridiculous defenses, it OHKO's the party if anyone is broken during its recast ability, and if it reaches 50% Force Gauge it will automatically counter any melee attack (physical or ranged) with a OHKO. There's plenty of players who have said this is the first boss that stopped them dead in their tracks from completing the Hard Mode story and had to skip it.
- Dare to Defy III on Global decided to bring Bhunivelze back, only with over twice as much health as the first time! What's worse, this was a special battle to fill in an otherwise sparse week, so no one knew ahead of time Bhunivelze would be returning. To add insult to injury, the banner that is attached to this fight features the full kit for Machina, who isn't even usable in this fight due to the 50% Force Gauge OHKO melee counter.
- The fifth Six Warrior fight has a large number of mechanics that are easy to screw up by accident and trying to follow them the intended way can be notably harder to do than just trying to avoid them: the enemy starts the fight by applying a buff that massively raises their damage and defenses and they increase their Force gauge very quickly by default, basically guaranteeing that they reach Force Time before you do. Once they do, they prevent your party from gaining any BRV and heal back 80% of the HP damage you do to them, making cancelling their Force Time a priority, but that can only be accomplished by dealing ranged damage with a Force skill while removing all debuffs from the party, which is something that only Mog and Balthier can do, and if there are no debuffs to remove, something that can easily happen despite the boss applying guaranteed debuffs to the party at the start of Force Time, it naturally can't be cancelled and it's better to restart. Once its HP has been reduced past 90%, 50% and 30%, the Heritage Golem applies a massive BRV and HP damage shield to the enemy party that needs to be broken with BRV damage 3 times each time, but it absorbs all elemental BRV damage other than specific 2 or 3 elements while it's up, and while it's up, the Protrusion Spheres paralyze the party after their attacks, forcing you to either use party members with specific elemental enchant auras or to use powerful non-elemental chararacters instead, with the latter probably being much simpler overall despite the implication that the former is necessary. And if you're thinking of getting past the HP damage shield with overwhelming HP damage and try to ignore the BRV shield, think again: none of the enemies can die until all 3 shields have been broken, and the buff provided by the large Protrusion Sphere also prevents that until it's dispelled, and you can't skip any of the shields either, since even if you manage to blow through all their HP with the first HP threshold shields still active, that just means you need to do the remaining 2 sets back to back while the enemy sits at 1%, refusing to die. While Balthier can steal and apply both of the enemy-exclusive buffs to the party, doing so in practice tends to be more trouble than its worth and his Force Time has hard-to-increase multipliers since it's built around the enemy repeatedly buffing themselves, which they don't do often enough.
- It seems to be the developers' intention to make every endgame fight associated with Shiva extremely difficult and annoying to beat: the Spiritus Shiva fight has you fight a pair of Xiuhtecuhtlis that start off the fight by using Earthen Impact+ each, which petrifies a random character each until their next turn and can't be redirected with Lock debuff or aura, which naturally makes the initial setup for the fight that much more annoying and they also use this attack at specific HP thresholds, easily ruining your Force Time setups, and if you push their thresholds too quickly during a burst or summon phase, both of them can end up using it twice if they're both still alive after it ends, which has the potential of getting your entire party petrified at the same time, resulting in a Total Party Kill. Once you lower their HP below 90%, they start using their main mechanic, Howl, a stacking aura that reduces the BRV damage you do to them and allows them to deal extra HP damage if it's stacked high enough, but more importantly, if their aura is at maximum level, they use Hopeless Rain, which is a Total Party Kill, and if their aura is at level 2 or higher, they cannot be killed. To lower the aura stacks, they need to be weak to one of the 3 main types of BRV damage and to be hit with that kind of BRV damage, which isn't too difficult, but here's where Howl+ comes in, which they use below 50% and 20%: to lower the stacks for this type of aura, it requires them to be weak to all 3 types of BRV damage (physical, ranged and magical) AND for them to be hit with an attack that ignores their DEF, something most characters can't do on a regular basis: as a bonus, if anyone in the party currently has a stacking normal buff or an overhead buff at 5 stacks or more, they gain a stack of aura for every player action, easily making the entire fight Unwinnable by Mistake if you happen to use a character with one if they can't lower it normally, although you can work around it by using a summon when they're almost dead since they can't gain aura stacks during a summon. Their Force Time is also extremely crippling, as it lets them recover their HP at the start of their turn, makes you unable to gain EX charge, and most importantly, has a massive 500% maximum BRV reduction for your party, essentially making it impossible for you to do any HP damage while it's up, and to cancel it, you need to deal BRV damage with a Force skill that ignores their DEF, which only 2 characters in the game (Edgar and Raines) can do by default. If all of the above wasn't bad enough, they also gain another buff below 20% HP that you can't get rid of that massively increases their defense and reduces all BRV gains by a further 90%, making it extremely difficult to deal damage through it. And finally, since it's a Spiritus fight, there missions to beat the fight with specific crystal color, weapon type and realm restrictions and trying to do all 3 at the same time leaves very few plausible parties to beat the fight with.
