Who is the greatest comic super villain of all time?  

For me, it has to be Joker. He's completely insane.

my favourite villian is and will remain (not sure LOL) theeeeeeeeee.........................JOKER!!!!!!!

The greatest comic super villian in a popularity poll is hard to determine. Each popular comic book title has both a hero and villain. You mention two of DC's villains and one Marvel villain. I happen to read more Marvel titles than DC so I could add, Mole man, Puppet Master, Loki, etc. But some of the other comic publishers Like Dark Horse and Image and Top Cow, etc. have heroes that are both part good and part bad, a conflicted hero character, so the "villain" label becomes more difficult to decide. I guess on a broader scale, the status of the hero influences the status of the villain and vice versa. To me, good literature is good literature. A well written comic with good characters and art are going to be interesting to me whether they are main stream popular or not.

The first three are a good start. For my personal top five, I would have to add the Green Goblin and Doctor Doom to that list. Other than Magneto, Joker, and Luthor, those two are among the most infamous villains in comic books. They have been part of many great stories and have done many heinous things. They are truly among the baddest of the bad.

Also, I would have to throw Sinestro on the list as an honorable mention. The Green Lantern that had gone bad might be up there with the top five. Also, Darkseid and Brainiac from Superman would be pretty big time comic book villains. Then if I am talking about Superman villains, I would have to kneel before Zod and throw him up there. Also from the DC books, Gorilla Grodd is also another one and the Gentlemen Ghost.

On the Marvel end, well Spider-Man has quite the list. Other than the mentioned Green Goblin, we have Venom, Doctor Octopus, the Hobgoblin, and many others. Mr. Sinister and Apocalypse from X-Men would be up there as well. There are just so many to name, but those are just a few of the great villains. Really, if I sat down and I had the time, I could make a top twenty or twenty five.

Also, I am going to throw the Shredder from Teenage Mutant Ninja Turtles fame on the list. Technically he counts, because TMNT started as a comic book years before the general public saw the original cartoon. And while the Shredder was killed in the first issue(and brought back later as a worm clone, long story), he is the number one villain when you think of the Turtles. Therefore, he deserves a nod, even though his villainy was technically cemented outside of the comic books.