The Injustice: Gods Among Us demo is now live on PSN and Xbox Live. Also released are items for avatars associated with the game on the Xbox Live Marketplace. There’s many available items from characters such as Wonder Woman, Superman, Batman such as logo shirts, etc, there’s two that have stood out as they hint at two more playable characters not yet announced. The costumes for Killer Frost and Ares can be seen below.

Every other available costume is for one of the game’s many playable characters, there’s a good chance we’ll be seeing these two in game as well, maybe as future downloads, maybe as unlockable items.

(via Joystiq)