Final Fantasy is one of the greatest video game franchises of all time. With the release of Final Fantasy 16 coming sooner rather than later, fans can't wait to experience another mainline entry in the series after years of hype. The action-heavy focus of the latest Final Fantasy game may split fans down the middle, but the many previews that have already been shown are pretty promising and have led to fans harboring high expectations for this title.

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Each and every Final Fantasy game features a litany of bosses that differ in terms of difficulty. While some imposing bosses end up being pretty easy in the long run, there are other encounters that can be quite a doozy to get through even if they don't seem all that threatening at first glance. The most notable examples of the latter are mentioned below.

8 Materia Keeper (Final Fantasy 7)

The Materia Keeper in Final Fantasy 7

The Materia Keeper is a boss that comes out of nowhere and is pretty strong to boot. Encountered when players are climbing Mt. Nibel, the Materia Keeper is no slouch and can decimate parties with its powerful magical attacks.

Players should definitely get some defense against Lightning, since the Materia Keeper's Trine attack will hit like a truck otherwise. Dealing damage while healing when required is key to succeeding against a boss that can be pretty nightmarish to overcome.

7 Dr. Lugae (Final Fantasy 4)

Dr. Lugae in Final Fantasy 4

The idea of a mad and goofy scientist being a hard boss is something that many fans don't really expect in Final Fantasy 4. However, Dr. Lugae ends up being a sizeable challenge despite seeming like a goofball when the encounter first starts.

From getting pounded by his creation Barnabas to becoming a robotic monstrosity that casts the annoying Reverse Gas, Dr. Lugae's tricks are numerous. He can easily take out a party that doesn't understand the mechanics of the fight, so players need to be quite wary while going up against this powerful foe.

6 Crawler (Final Fantasy 10)

The Crawler in Final Fantasy 10

Given the sheer number of powerful figures and massive monstrosities in Final Fantasy 10, the last thing that players would expect to cause them some trouble is a piece of Al Bhed machinery. However, the Crawler ends up being pretty tough to fight mainly because it blocks magic and forces players to resort to physical attacks instead.

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The Crawler is a pretty tough boss fight where players need to unleash their most powerful physical attacks to get through a grueling battle. It doesn't help that the Crawler itself hits like a truck and necessitates setting up defenses or healing at regular intervals.

5 Jumbo Cactuar (Final Fantasy 8)

Jumbo cactuar in Final Fantasy 8.

Final Fantasy 8's Junction system trivializes many of the game's encounters. However, the game can still ramp up the challenge with its many boss fights, especially when the player doesn't expect this in the slightest.

A party that's trying to acquire all the junctions in the game will eventually trigger a battle with the Jumbo Cactuar. Its 10,000 Needles attack serves as an instant KO, and players need to be wary and not be taken out easily while trying to get this Guardian Force for themselves.

4 The Tentacles (Final Fantasy 6)

Tentacles in Final Fantasy 6

Final Fantasy 6's World of Ruin is a unique segment where players have to reassemble their party before mounting a serious challenge in Kefka's Tower. While trying to liberate Figaro's Castle and free up its machinery, players start a fight with four tentacles that have stopped the gears of the castle from moving.

The battle is tough mainly because the Tentacles can grab party members and suck their life essence. It's a trying encounter, and players need to heal at regular intervals and unleash as much damage as possible to take out these foes once and for all.

3 Friendly Yan (Final Fantasy 9)

Yan in Final Fantasy 9

Technically, the Friendly Yan isn't really a boss fight but a unique version of the Yan enemy that is encountered during the Friendly Monsters questline. Players who want to challenge themselves can decide to attack this foe, initiating a super boss encounter that is extremely challenging.

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The Friendly Yan has high evasion stats and hits like a truck, meaning that players will have their work cut out for them while challenging this foe. Players need to use strong attacks that ignore the Yan's defenses while healing their own party at regular intervals if they want to stand a chance of defeating this powerful enemy.

2 Atomos (Final Fantasy 5)

Atomos in Final Fantasy 5

Atomos is a boss that looks pretty imposing, yet hits even harder, pulling off a Comet attack out of nowhere that hits the party for massive damage. After KOing a party member, Atomos tries to suck the party member in and permanently remove them from combat.

Suffice it to say, this can prove to be quite a headache, especially since the strategy for fighting this boss involves letting a character get KOed to keep Atomos busy while the party wails on them. As long as too many party members aren't lost to the might of this boss, players should be able to get through this encounter by the skin of their teeth.

1 Lord Ochu (Final Fantasy 10)

Lord Ochu in Final Fantasy 10

The Ochu is one of the toughest and most iconic enemies in Final Fantasy. That being said, no one would expect a super-powered version of this regular enemy to pose such a massive headache.

The Lord Ochu that players fight in Final Fantasy 10 ends up being one of the most annoying bosses in the game. The Poison effect is never welcome, and its use of Earthquake after awaking from a rejuvenating slumber hits for a ton of damage too.

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