I think INTJs make better villains because they're naturally strategic and possess a level of emotional self-control that is both creepy and admirable. Also, dry wit always makes for a more lovable villain.
"Sentiment without action is the ruin of the soul." - Edward Abbey
For an INTP villain, I would suggest Curt Connors, a.k.a. the Lizard. He's principally a scientist working on something that will benefit himself personally, but it goes horribly wrong.
Problem: Curt Conners may be an INTP, but he and the Lizard are not the same, just like Dr. Jekyll may well be INTP, but Mr. Hyde is most assuredly not. Hence, it isn't the villain that's INTP. In the case of Dr. Jekyll especially, it's the protagonist.
I guess, from a utilitarian standpoint, where only outcome matters, Conners and Jekyll are evil. But from a Kantian(motivation/duty) or Aristotelian (character) standpoint, they're actually very good people who wanted to help the world.
They're practically your staple villains, with a few ENTJ's and other types occasionally thrown into the pot. Probably, apart from their NT, because of the way they often rebel against society in a way that ENTJ's and INTP's don't. Anyway, which do you think is the best at being evil?
Some INTJ villains include:
Darth Sidius (Maybe Vader also)
Some ENTP villains include
John Simms as The Master
Tho joker (Though I have heard a pretty convincing argument he was INTJ)
Uh... hit a mental blank but there are quite a few more. Anyway, which type do you think are more effective and/or more entertaining as villains?
I'd like to see the argument about the joker being INTJ. Doesn't seem at all likely to me. He almost seems like a stereotype of ENTP.
I think INTJs make better serious villains and ENTPs make better comedic villains.
Going back a few pages, while I agree the Joker is ENTP, are we saying it is impossible for an INTP to have a non-knowledge based motive? Why would the joker being sadistic and enjoying inflicting pain stop him from being INTP?
And Johnny the homocidal maniac is an INTP villain I think.
And I prefer INTJ villains, but ENTPs can be good too.
Mastermind figure conveys too much reverence and respect. The Trickster is much more interesting and can even shoot himself in the foot as he goes along. We don't have to wait for the finale to see the Mastermind showing his weak defeated face....and the trickster is least likely to show it at all..