Of those presented in the list, the best is Johan. But I would add Griffith here.

DIO

Frieza. All hail Emperor Frieza!

I would have voted for Frieza earlier, but I honestly don't like the direction he's currently taking in Dragon Ball (I hope they don't redeem him). I would have voted for Light instead, had it not been for his pathetic defeat at the end of the manga/anime. AFO strikes me as a good villain but I think it is an exaggeration to say that he is one of the best of all time. And I haven't seen either Akame Ga Kill or Date A Live. So my vote goes to Johan, possibly one of the best-developed characters in all of fiction. Although I still think that Shogo from Psycho Pass is one of the best villains in all of anime.

The ending the anime gave Light redeemed him in my eyes with its more sympathetic tone but his breakdown beforehand was pretty pathetic and I still prefer Frieza.

I like my queen esdeath, BTW I more like nihilistic villains, so I'll choose Isaac and Johan.

Frieza got me to like anime but cell is the real reason why i begin to watch anime overall.

Imagine voting for generic shōnen villains like Frieza or… All for One, or “muh big‐tiddy anime waifu!!” fan service characters like Esdeath, when they’re on the same poll as Johan.

Frieza, the superpowered, cackling, androgynous alien lizardman who blows up planets and whose personality is that he’s a sadist, versus Johan, evil and nihilism incarnate (while still only a human being, albeit nearly as inhuman as possible) whose character explores the real‐world plausibility of a concept like “pure evil” via red herrings that constantly provoke the viewer into questioning what made him into what he is (if anything) and what could’ve made him different. His complexity stems not from moral ambiguity since he’s obviously depraved and horrible, but from the ambiguity of his circumstances and nature along with the subtle hints at a philosophy beyond simple nihilism (e.g. fatalism); what makes any of these other characters complex?

Frieza is the kind of character that everyone can agree is just an asshole, but Johan’s success as an Antichrist‐like figure—the Antichrist being a sort of false messiah, being very agreeable and likable to the general populace in order to sway them to his side—is so great that there are viewers who sympathize with him, who think he isn’t as bad as he is or could be redeemed, or go as far as to romanticize him. It’s like he’s emotionally manipulated the viewers themselves.

I haven’t watched most of these, but from what I’ve seen and gathered: Light seems like a plot‐armored protagonist (even more so than Johan’s plot armor as an antagonist, which is more justifiable) whom people think is a genius because he’s literally omniscient and the plot is written to suit him, Isaac is an edge‐lord who’s the embodiment of quantity over quality in terms of crimes and all‐around seems like the writers tried way, way too hard to make him the ebilest character ever without giving him much substance, and My Hero Academia is absolute weebshit garbage that requires no further consideration. Johan is simultaneously more vile and more compelling than any of these.

Johan wins.

Westcott is more vile than Johan for sure (he’s basically Johan cranked up to eleven, they’re very similar but Westcott is definitely worse). I agree Johan is better written though, he actually had me initially feeling and for him before he showed what a monster he really was.

Frieza got character devolpment in the Tournament of Power and has mellowed out which made his character better in the eyes of many (you don’t watch Dragon Ball so I understand why you wouldn’t know this).

I don’t know about that. Personality and motives matter just as much as actions—not to say that Johan’s actions aren’t pretty egregious too, given his mass murder and psychological torture of children. Being an edgy sadomasochist with a ridiculous body count doesn’t really make you worse than someone who is emotionlessly cruel with nothing to gain from it. At least Westcott’s motivation for his crimes (to some extent) is that he enjoys it, in addition to having some sort of vision; what’s Johan’s excuse? Westcott sees human beings as evil rather than himself and is fueled by a sort of supremacism, whereas Johan has indiscriminate, limitless malice and knows he’s the worst human alive, is indifferent to it, and needs no justification. I don’t see many fictional characters that are truly (and deliberately) evil just for its own sake; it just serves to make him more inhuman.

All Johan wants, initially, is to recreate Kinderheim 511 on a global scale—i.e. for civilization to crumble and to reduce all humans into savages killing one another until nobody, nothing, but him remains. Furthermore, something made Westcott the way he is and we know of what it is, whereas Johan appears to be evil for no real reason. They’re also not very much alike aside from being considered nihilists (although I don’t see how Westcott qualifies as one if he is a supremacist who believes in evil himself).