I'll probably go with general opinion & say Joker.
Not the movie versions but the crazy bad-ass comic version...no one comes close to his sheer level of lunacy.
Theres loads of comic Villians I love but Joker has be my favourite.
Darth Vader
Jaws (If that counts)
Predator
Jack Torrance from The Shining
Norman Stansfield from Leon
Brick Top from Snatch
Bill Cutting from Gangs Of New York
Anton Chigurh from No Country For Old Men
Hannibal Lecter
Could of been on my list
I loved Gary Oldman as Drexl in True Romance but he's only in the movie for 10 mins but what an impression he makes & then there's Darth Maul, should of been on my list but Lucas killed him of within one film. He should of lasted the Triolgy & I didn't like how he got killed.