Fun enough game with 6 game modes and with some Left 4 Dead vibes. It comes with several characters to play as, with some that have to be unlocked. By hosting the game, you have several available options to tweak the difficulty of the campaign.

The game can be played in both solo and in co-op. Although it's nice to have solo to play with AI (by the way, even with the Bot Intelligence in Expert, they are pretty stupid), it's always better to play with your friends!