I'm no expert, but isn't the Hulk 100% invincible and undefeated? I'd put all the money in the bank on the Hulk over any other superhero ever.
He got beaten by Iron Man in Avengers II. While knocked out he could be launched into space or something.
Lilith Drake would totally kick ass. Part vampire, part human with all the strengths of a vamp and none of their weaknesses.
Ok ok.. Please do suggest TWO characters!!! ... Deadpool vs Pikachu.. Deadpool is funnier but Pikachu is cuter.. I say Pika electrifry his ass *Note: I am slightly biased cos my name has Ash in it
Master Chief vs. Samus? My money is on Chief. He has access to a wide variety of powerful weapons and his armor and augments are extremely high tech. He is battle hardened and has survived a nuclear explosion, multiple falls from space, and the death of his one love, Cortana.
Lilith Drake vs Batman Lilith wins cause of her powers of hypnosis, superhuman strength and speed. Plus she morphs into a bat AND controls bats. She is going to totally control Batman. I pity him...
May I suggest a KY Jelly fight between Carmen Ibanez from Starship Troopers and Black Widow from the Avengers. I don't care who would win. I do hope that each of them would end up on top at least once.