Video game villains are typically sorted into one of two categories: super eccentric and goofy, or super intense and terrifying. Anyone could name a popular RPG villain that falls into each category, such as Bowser from the Super Mario Bros. franchise and Darth Vader from Star Wars. However, an antagonists' appearance might not be a good indicator for how hard the boss battle actually is.

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There are plenty of funky, weird, or underestimated villains who actually pack quite a punch and can take down the story's hero in an instant. These RPG bad guys are the toughest of the tough, even though they really don't look like it. Be prepared for a long fight!

10 Kefka (Final Fantasy VI)

He may be dressed as a funky looking clown, but Kefka is known to be one of the hardest to beat bosses in all of Final Fantasy history. His appearance definitely throws people off; he wears full face paint, the most colorful, vibrant poofy clothes, and giant feathers in his blonde hair. However, Kefka is filled with a desire to become the strongest magic wielder in existence to bring utter chaos to the world. Don't let his long painted nails throw you off, this antagonist can easily take down his foes.

9 Cow King (Diablo 2)

This hidden boss in Diablo 2 can be found in the "Secret Cow Level," which can only be opened once the player has completed an entire difficulty level. There are plenty of Hell Bovines, or murderous bipedal cows, that players have to fight in this level, but this Cow King is the toughest of them all. The battle isn't very easy to win, even though it is a cow, so players need to be prepared for his enchanted lighting and magic resistance. What makes this boss even worse, is that in order to complete the Cow King's Leather set, players have to defeat him three times, once in each level difficulty.

8 Karstaag (Skyrim)

This transparent foe may not look as daunting as some of the other villains throughout the world of Skyrim, but he is definitely not an easy one to take down. He's got big, meaty fingers and doesn't even appear to be in the physical realm (since he's in the form of a ghost), but this guy can definitely pack a punch.

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The frost giant is a secret boss and can only be found once players reunite his skull with his skeleton. His ghost will appear and he will reign fury on his summoner, with powerful stomps, blizzards, and ice wraiths. Who knew a dead guy could create so much havoc?!

Dark Link is a reoccurring bad guy in the Legend of Zelda franchise. His more iconic appearance is in the Ocarina of Time, where the real Link has to roll around avoiding attacks from this speedy little doppelgänger. After facing some of the toughest challenges and puzzles in the hard-to-beat temples in OoT, this mini bad buy doesn't seem like he'd be too tough. However, he does not let the real Link off the hook so easily. He mirrors Link's tactics and deals heavy blows, leaving the player to have to deal long distance attacks to avoid the deadly Dark Link's blade.

6 Emerald Weapon (Final Fantasy VII)

Despite his towering size, the Emerald Weapon looks like a giant toy action figure. After facing the arguably easy-to-beat Omega Weapon in FFVI, fans may not think much of this Weapon. But do not be fooled because this green giant is recognized as one of the hardest enemies in Final Fantasy history, along with being the toughest in FFVII. This level 99 boss is found at the bottom of the sea and boasts a whopping 1 million HP.

5 Sephiroth (Kingdom Hearts 2)

It's true that Sephiroth is one of the deadliest antagonists in Final Fantasy, but in the universe of Kingdom Hearts, he doesn't seem to post much of a threat. Throughout the main game, Sephiroth is kinda just thrown in the story to make Cloud all depressed and angry, and Sora leaves to deal with much more prevalent enemies like Xemnas and the Organization.

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It's not until the game is over than fans can see how insanely tough Sephiroth actually is. He is a secret boss that will deal so much heavy damage, unprepared players can be wiped out in seconds. Ask any KH fan about this battle and they will likely start seething with anger. He's arguably a stronger boss in KH2 than he is in Final Fantasy!

4 M. Bison (Street Fighter 2)

With a comically shaped smile and a bright red uniform with a floppy hat, M. Bison looks like an overgrown Mario bro. The protagonists in Street Fighter all boast giant muscles, sleeveless shirts to show off their bulging biceps, eery scars, and scowling faces, making them way more intimidating than this big villain. However, M. Bison is a super hard boss to beat in SF2! He doesn't let his corny appearance overshadow how strong and skilled he really is.

3 The Yellow Devil (Mega Man)

Not that Mega Man in all of his 8-bit glory looks super intimidating, but he does look way cooler than his cartoonish antagonist. The big, round body paired with the single, little red eye doesn't help make The Yellow Devil look very scary. The big, menacing robot created by Doctor Albert W. Wiley makes a very tough foe in the original Mega Man, even though he may not look like much. He reappears throughout multiple games, but always looks very soft, squishy, and almost cuddly.

2 Toad Prince (The Witcher 3)

The name "Toad Prince" makes you think that this enemy will look like he's straight out of The Princess and the Frog. However, this cursed amphibian is big, nasty, spooky, and is way harder than players are prepared for.

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Though he's only the first boss battle from the Hearts of Stone DLC, he's one of the toughest! He's huge and poisonous, and filled with rage towards the witcher. In the end, he really is just a prince who was turned into a toad by magic, but that doesn't mean his boss fight is easy.

1 Undertale (Sans)

Sans the Skeleton is easily the most famous character from the game Undertale. His name comes from the meme'd font, comic sans. He is a quirky skeleton who loves puns and serves as either a goofy side character or the main villain/final boss depending on the decisions the player makes. His boss fight is notoriously hard and anyone who has faced him will agree.

Fans across the world have shared their experiences fighting Sans, with some claiming it takes dozens of tries before they can take this goofy boss down. Geeetttt dunked on!!!

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