Boom Face

Boom Face is a first person shooter that makes reloading a bit more frantic. You've got to remember if you've got a round in the chamber, and manipulate your gun's action yourself. In addition the shotguns have three different types of rounds and you better remember which order you loaded them! Blow your friends face off, or try to beat your own high score! This game can be played locally with a shared screen, over the internet, or any combination of the two with up to seven friends (8 players total). You can use Xbox controller(s), or the game will revert to mouse and keyboard controls. You must have one controller for each player in order to enjoy local multiplayer.

Game modes:
Challenge (Single player): Set your high scores in 30 different single player maps.
Death Match (Multiplayer): 5 different multiplayer maps to compete in. Every man for himself.
Team Death (Multiplayer): An additional 5 diffeerent multiplayeer maps to compete in. Score more kills than the other team to take the win.
Wave (Multiplayer): 4 more maps, but this time you fight together against waves of incoming enemies. Get as many kills as you can. Technically, you can play this mode by yourself, but good luck!

Source: Steam Store Description