The Xbox Network is particularly generous with us these days. They also sent us Zombie Army Trilogy on Xbox One, the game also being available on PS4 and PC. This title actually regroups several mods which were originally planned for Sniper Elite V2 and is now a stand-alone full of content. Alone, you'll most certainly have a hard time as it's quite a challenging - and repetitive - game, but if you have friends to play with, it will be a lot of fun.