Tobi from Naruto is one of mine, due to the fact he is everything that Naruto isn't, all because of a right upbringing filled with friends and love, versus one of loss and jealousy for Tobi, and seeing the woman he loves die right before his eyes.
Otherwise it's Hao Asakura from Shaman King. He's so powerful, not a person stands a second against his magnitude. And in the end, he wins, and the shamans have to ask him to revive everyone who he killed.
Fucker becomes God. Yeesh.
Alexander Anderson from Hellsing would be pretty high up on my list, same with Scar from FMA/Brotherhood.
also you've gotta love Delphine Eraclea from Last Exile, such a fucking psychopath...
Reading A Song of Ice and Fire is like playing with an adorable puppy, then someone comes up out of nowhere, shoots the puppy and punches you in the face.
Stands in front of 100 enemies with 10% health left "Myeh, I'll save my potions for when I REALLY need them." - every rpg player ever.
Anime-esque, but Fire Lord Ozai.
I actually almost feel sick that people mentioned Aizen.
"Everything you have done up to this point (the past 300 or so episodes) all went exactly according to my plan."
Ugh, really? Really?
Anyway, by far the best one in recent memory would be Kyubey.
Aizen - Bleach
Stark - Bleach
Schrödinger - Hellsing Ultimate
The Major - Hellsing Ultimate
Alexander Anderson - Hellsing Ultimate
Father "The Dwarf In The Flask" - Full Metal Alchemist Brotherhood.
Light - Death Note.
Those are the only ones I can think of atm they all kinda tie as my fav villain.
You knew he would lose and so did he that is what made it interesting.
He was more of a smart villain then a brute strength villain kinda why I liked him. Even he knew if he fought the head caption one on one he would lose he even admitted it that is why he sealed away his power.
Not to mention the whole "i take off my glasses and spitcurl my hair and bam! im suddenly so different and evil!" thing.
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Gluttony FMA:B. He's just a likable person.
Sloth FMA:B. Armoured cars? Mendokuse/move it.
Also Orochimaru from Naruto. I like his voice and his style. He's psycho to the bone, a true villain.
"I don't have a complete healing set yet, but I am healing capped and MP5 capped, so I'm good."
I liked the villains from FMA: Brotherhood. Suitably creepy (Lust, Gluttony), or suitably warped and interesting (Greed), and Dwarf in the Flask had reasonable motivations and actions
I enjoyed Bleach to some extent, but Aizen was a lousy villain. He didn't start lousy, certainly, but it never seemed like Kubo had a solid plan in mind for him.
I mean, compare him to Blackbeard for instance (One Piece). You hardly see both, they're both implied to have a great power, they're both implied to be huge threats, but Blackbeard is way more fleshed out and interesting, and he actually does something very directly that influences the main character (though he didn't plan it that way).
My favourite villain so far would be Tyki Mikk, from D Grayman. Very confusing mix of stone cold killer (his Noah side) and warm affection (his Human side) to his fellow Noah, and his human friends.
For me its Nagato/Pain from naruto. I have a thing for antiheroes/fallen heroes.
Also Father guy from FMA:B.
I sat and thought about this one for a bit and I couldn't come up with anyone whom I thought was heads and shoulders above Dio. There were villians whom I thought were decent like Shishio (Kenshin), Dwarf in the Flask (FMA:B), Sharon Apple (Macross Plus), Sid Vicious (Cowboy Bebop) but none of which I would consider better.
I think part of it was because of how mysterious he was. You know he was powerful but you didn't know exactly why he was so powerful. And I think it was that mystery is what makes him better than the rest.
Wrath, FMA Brotherhood
People have mentioned several of the homunculi and Father, but Wrath stands out the most for me. Why?
First, because he remains unbeaten. At no point do the good guys face him down equally. Scar mentions that if it had been a remotely fair fight (i.e. Bradley wasn't wounded, missing his eye, and about 20-30 years past his prime) that it wouldn't have even been a contest.
Second, his final scene is perfect. FMA's main theme is really about hubris and its consequences, and nowhere is that better exemplified than Wrath's defeat. He declares, "There is no God in this world!" as he stands victorious over Scar. At that very moment the eclipse shifts through the hole in the ceiling, reflecting off his blade and blinding him, resulting in his death.
Third, there is a sort of honor in him. He mentions that he has real pride in being a homunculus. When he's vanquished he doesn't suddenly fall to pieces. And when Lan Fan tries to lecture him he just cuts her off. This isn't some guy that at the end is going to fall apart, seeing the error of his ways at the hands of a teenage girl. He lived a long, complex life and has little regret in his actions and will not be pontificated to. These attributes are the sort that you would normally associate with the protagonist, and which make him much more striking than most villains.
Balalaika, Black Lagoon
Balalaika isn't a normal villain in the sense that she doesn't oppose the main characters. She doesn't have any evil plans which must be thwarted or goals which will destroy the world. But I find her more chilling than most of the super psychopaths in anime because she's so evil in a real-world sense. She's involved in your standard drugs and weapons, but has no qualms against assassination, torture, and even darker pursuits. I think perhaps this is the most disturbing scene, causing even her hardened second to comment, "That was hard, Capitan. Just watching gave me the chills"
most asshole villain: envy from fullmetal alchemist brotherhood. switching to some1 dearest to the victim before he kills them so that they cant fight him
most badass villain: wrath from fullmetal alchemist brotherhood. if you know him you know it's true
most evil-mastermind villain: gonna go with aizen. you never knew what that bastard was gonna do next
someone else might have gotten it wrong.