Lex luther 10 times. The other time he was cloned and came back as his son and then there was a virus killing clones and he was saved and looked like the old lex. But lex actually died once. The radiation from the kryptnite ring did him in (thus the whole clone crap)I said major "vilain". How many times do you think Lex Luthor was though to be death in the last 40 years, surely more then Magneto. Sorry, but Marvel and DC are exactly the same on this. Beside, what is death in a fantastic universe that do not obey the law of science ?
But i'm sorry the one thing marvel can never be forgiven for is the whole clone of spiderman shit they pulled. That was the worse comic I have ever read in my life and its crazy that it was ever made.