Marvel: Ultimate Alliance 2 is currently my favorite game. I also have Halo Wars, Mini Ninjas (it's freaking awesome), DJ Hero and I actually need to get back to my Transformers: Revenge of the Fallen game. It's a really fun game and all, but I got distracted from it about seven months ago and forgot to get back to it. XD
But yeah, M.U.A.2 is epic and a blast to play. Once you get the hang of switching between them all, of course. Spider-Man smarts off constantly and when he's about to be K.O.ed, he goes, "My spide senses are telling me I'm gonna die..." Captain America is lame, but I never thought much of him. Wolverine is powerful... That's it. He's just strong. XD And Ironman can fly, so I adore him. Plus he has the coolest specials with the other people. As for the unlockables, can't comment until I get all of them.