Anakin Skywalker. All he ever wanted was to save Padme and gain immortality.

I have to agree with others here who like Heath Ledger's portrayal of the Joker. His is the darkest, most layered version of the villain. It has no camp at all, unlike Nicholson's, who was a good baddie, but still patterned after the Cesar Romero version from the original Batman TV series, right down to the cackle. LOL! Also agree with others here that Ledger's loss was huge.

Zec Chilovek
Completely amoral; no conscience; profit driven.

Bane as played by Tom Hardy in The Dark Knight Rises
The Joker as played by Heath Ledger in The Dark Knight
The Penguin as played by Robin Lord Taylor on Gotham and Danny Devito in Batman Returns
Loki as played by Tom Hiddleston in the Thor and Avengers series
Agent Smith as played by Hugo Weaving in The Matrix
Hannibal Lecter as played by Anthony Hopkins in Silence of the Lambs
Tommy Devito as played by Joe Pesci in Goodfellas
Cobra Kai Sensei and his students from The Karate Kid
Doomsday
Freddy Krueger
Jason Voorhees
Michael Myers
The Terminator
Gollum (kind of annoying too lol)
Gunnery Sergeant Hartman as played by Lee Ermey in Full Metal Jacket
Leatherface
Megatron
Surtur from Thor: Ragnarok
Hela as played by Cate Blanchett from Thor: Ragnarok was pretty bad ass

I don't know much about the character, but I suppose Thanos will make my list after I see Avengers: Infinity War. He's supposedly one of the top most powerful villains ever.

All of them are either powerful, creepy, diabolical, quirky, assholish, or evil lol. Makes for good entertainment.

I have always loved Twoface. He is one who plays his life based on flip of a coin.

Sauron and Saruman with a big honorable mention to Darth Vader

Real? Probably Kim Jong Whichever. Easy to make fun of, torments and prods the US, bound to die soon.
Fictional? Cobra Commander. Easy to admire, torments and prods the US, bound to take over the world soon.

Hannibal Lecter

terminator

Lately my favorite villains are the Minions.

Snydley Whiplash.

Dark Vader

If you want an overabundance of amazing villains watch 'Gotham'. Batman always had the best villains.

V from V for Vendetta.

The Brain.

God

Darth Vader.

Yosemite Sam. Bugs' best foil.
Lee Marvin's character in the Cowboys. He shoots the Duke in the back!
Richard Nixon. So complicated.
Lee Harvey Oswald. One mixed up mother goose.
Mr Potter from It's a Wonderful Life. Lionel Barrymore at his cruelest.
Aku! from Samurai Jack.

Steven Miller the Joseph Gobbles clone. Not because he's my favorite, but because he is the worst.

Negan from The Walking Dead! Delightfully diabolical and easy on the eyes

Jack Torrance (The Shining) was very creepy!

Danger 5's Hitler

The Perfect Heil Hitler
2 parts dark rum
Crushed ginger
Fill with orange soda

I like female villains that smile and bat their eyes before plunging the dagger between his ribs, not the obvious ones like Cruella Deville from "101 Dalmatians" or the wicked witch in "Alice in Wonderland." More like the Mata Hari type who lures them in with her sexuality before twisting them around her little finger. Their cunning and deviousness make them compelling.

I would say the humble narrator in The Clockwork Orange.