Cletus Kasady, AKA Carnage, is making his way to Marvel Ultimate Alliance 2, and he's much more than another Spider-Man clone.
Carnage is what happened when comic book writers looked at one of Spider-Man's most powerful foes, Venom, and decided he just wasn't dangerous enough. Marvel describes Carnage as a total psychopath with no sense of honour, where Venom is a slight psychopath with a fair to middling' sense of honour.
Over at the official Marvel Ultimate Alliance 2 web page, lead animator Adam Olshan assuages players concerns that Carnage winds up just another version of Spider-Man or Venom.
We used the word "vicious" a lot when talking about how he should look. "Crazy" too, because of the background of who he is and what he is. I worked mostly on his basic melee combat. That's when we really pay attention to how we can differentiate that character. Spider-Man needs to be agile & springy. Venom was more of a bruiser, like a huge jungle cat who attacks with lethal clawed swipes. For Carnage, we wanted him to feel as quick as Spider-Man, but as dangerous as Venom (or worse). We ended up with a very "slashy" character. Carnage is like a lunatic knife fighter: cutting people up quickly and messily, without much concern for how he looks doing it.
As of right now, all we know is that Carnage is coming to the PlayStation 3 and Xbox 360 eventually. He sounds interesting, but Carnage remains one of my least favourite Spider-Man characters of all time, so unless they put him in a pack with someone more interesting, I probably won't be biting this time around.