These are the Game Modes in Aliens: Colonial Marines:
Multiplayer
Play multiplayer play by connecting online. You can also play locally by connecting multiple PC’s via LAN.
Co-Op Play
Campaign mode can be played co-operatively by up to 4 players. Clients can join in and leave the campaign any time. However, the Host must remain in the game in order for it to remain active.
Versus
Play two rounds of team battle, where each team takes turns as Marines and Xenomorphs to battle against each other.
Choose a game mode and map, select find game and the player will be automatically sent into a game. Network mode can be changed through the Advanced Options menu.
Versus Modes include: