I am actually relying on this subject alone being like Armageddon. It'd be cool If both players can choose the alternate costume and second player would still have to be in a different color, because knowing MK, second player is always in a different color no matter what costume you wear, but I also hope like MK4, You can choose the color or the costume for the character, but I'm banking that they won't considering MK4 being "a disaster".
