I'd have to go with Darth Vader. A great mini-series just ended starring Vader called Darth Vader and the Ghost Prison. Excellent series which I highly recommend. One of the best endings in mini series I've ever read!
I've been reading a bunch of my old New Teen Titans comics, and I gotta say Deathstroke is a major highlight of the series. The whole Judas Contract stuff alone is awesome enough. If not Deathstroke, how about some love for the Flash villians?
Thanos by a landslide. Nobody threatens the universe like the mad Titan does.
I'd have to go with Darth Vader. A great mini-series just ended starring Vader called Darth Vader and the Ghost Prison. Excellent series which I highly recommend. One of the best endings in mini series I've ever read!
Though not wholly original, I'd still have to say Joker.
Any nameless villan who showed up in Solo Avengers, there was a new one every month.
Gotta go with Joker; just a timeless character that'll be around forever and ever