The latest Games with Gold on XBOX 360 is Gotham City Impostors!
I've played this game some time ago but I didn't get too far into it before stopping for some reason. So when I saw that it was on Games with Gold on XBOX 360 it had to be downloaded STAT! I love this game. Partially because I love anything that has anything to do with Batman, even if they aren't really him. Gotham City Impostors is a first person shooter, which I love also. The premise of the game is simple. There are two factions. The Bats, and the Jokerz. You have the Bats who are Batman impostors, and then you have the Jokerz who, you guessed it, are Joker impostors.
Going head to head either against CPU or other players is so much fun! My 5 year old loves playing this game (but then again, he also loves anything that has anything to do with Batman too). If you haven't downloaded this game, get it while it's still free!!