Boss fights are meant to be a test of the skills you acquired over the course of the game. Every fight is meant to prepare you for the ultimate challenge awaiting you via bosses. But sometimes game developers get a little gung-ho about making these moments so challenging they just become annoying.

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Boss fights are meant to take longer than fighting a standard enemy, but the ones on this list take the cake by being excruciatingly long battles of attrition. Whether it’s quirky game mechanics, overpowered spells, or ridiculous health bars here are some of the longest boss fights out there.

10 The Immortal One: Lost Odyssey

The first game to kick off the list is The Lost Odyssey, a lesser-known Japanese RPG that had players forming teams of Immortals to defeat their enemies. The Immortal One was a boss that had ridiculous amounts of health and devastating attacks.

Even with a high leveled team, the player was doomed to slowly chipping away at its health. Imagine playing a clicker game but each click takes a few seconds to perform and you’ll have an idea of what fighting this thing was like. You needed a good hour or more to beat the Immortal One.

9 Nyx Avatar: Persona 3

The Persona series has gotten better over time by minimizing excruciating boss battles via in-game mechanics or simply toning everything down. But in Persona 3 players were subjected to a torturous fight against Nyx Avatar that took a little over an hour.

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Nyx Avatar had fourteen phases that needed to be beaten and each one had little tweaks and variations to how the boss fought the party. In her final form, she could reflect damage, dish out high numbers on her own, and charm one of your party members into healing her.

8 Abyssion: Tales Of Symphonia

Abyssion from Tales Of Symphonia was not only an annoyingly long boss fight, but reaching him took forever. You could only face him after retrieving all of the Devil’s Arms items.

What made him such an abysmal boss to face is that he often used your own skills against you meaning the better your setup the better his setup became as well. If you managed to retrieve all the items then definitely take a break before turning them in as the boss battle triggered immediately afterward takes more than an hour to complete.

7 Yiazmat: Final Fantasy XII

Yiazmat made a name for himself for being a brutal boss in Final Fantasy XII. Boasting 50 million health points he takes quite a while to whittle down. Even worse is that once his health is below 50% your party’s damage is capped off at 6,999 which means the second half of the battle takes even longer.

You also needed spell interrupters on your team as Yiazmat has certain spells that recover 100% of his health. This boss fight takes about an hour to beat assuming he never has a chance to heal, if he does you’re looking at a long fight in an already long game.

6 Boss Rush/Yami: Okami

Okami has a large number of bosses that you’re meant to defeat before reaching the final boss of the game, but once you do you’ll be blindsided by the fact that you have to face every single one of those bosses again in a boss rush.

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Once you’ve completed this tedious task, then you go up against Yami and her multitude of forms. While this isn’t the most complicated of fights it does take a solid two to three hours to complete even if you know what you’re doing.

5 The End: Metal Gear Solid 3

This is one of the few bosses on this list that fans felt was a relatively fun experience in spite of how long it took to beat. The End is a legendary sniper who stalks you throughout the game and seemingly appears out of nowhere to wreck your day with tranquilizer darts.

Once you face him it’s an incredible test of stealth and patience before defeating him. Overall you’re looking at two to three hours of gameplay. If you want to beat him faster then pause the game mid-fight, wait a week, and come back to find old age has taken its toll effectively ending the fight for you, suddenly that two to three hours doesn’t seem so bad.

4 Adamantoise: Final Fantasy XV

Most bosses on this list are simply a means of finishing the game or completing a challenge, the Adamantoise in Final Fantasy XV is actually a treasure trove of useful items, assuming you’re patient enough to beat it.

With over five million health points, the Admantoise is a superboss that takes a lot of patience to bring down; even with a high-level team you’re looking at three to four hours before cracking his shell. Sounds annoying until you learn that the developers intended for the fight to take 15 hours.

3 Pandemonium Warden: Final Fantasy XI

The Pandemonium Warden from Final Fantasy XI was a true boss battle in the beginning. When it was first released players from the Beyond the Limitation clan spent nearly 18 hours trying to bring it down only to give up as their bodies broke down from exhaustion and health problems.

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This prompted Square Enix to ramp down the difficulty and even introduce a two-hour timer causing it to despawn if it hasn’t been beaten in that time. The difficulty of this boss was a ridiculous health bar and 20 forms it changed into during the fight.

2 Absolute Virtue: Final Fantasy XI

Final Fantasy XI had Absolute Virtue which forced players to throw their hands up in frustration after they spent gargantuan amounts of time trying to beat it and being unable to. In this case, it’s said that players spent more than 30 hours trying to beat it.

Eventually, the developers caved and made the hardest boss in the franchise easier by scaling back its stats and raising the level cap from 75 to 99. Now the boss is a quick fight for great loot, but back in the day it was unreal.

1 Yggralith Zero: Xenoblade Chronicles X

This is easily one of the longest bosses to take down in singleplayer as it requires the cooperation of other players in their own singleplayer games to bring down. It has millions of RP or health bars and each defeat will remove one of those health bars.

The entire player base must take it down over and over again to finally kill it. Coupled with that fact that it currently takes the fanbase several months to spawn one and most are interested in appendage farming rather than killing it, it takes forever to bring this brute down. It can take anywhere from five hours to an entire week depending on who’s playing at the time.

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