In Alien Shooter 2, the Earth's resources have been depleted somewhat due to a biological experiment gone wrong. As a result, the Colonial Security force (CSF) must be brought back from the dead. Upon arrival on the planet, the aliens appear and begin annihilating the remaining Colonial soldiers. It soon becomes apparent that these creatures are not fleshy and are in fact a group of alien warriors. Two squadrons of Colonial troops are sent to investigate the destruction, and encounter a group of Xenomorphs which were injected with a synthetic life form. The squadrons destroy the alien invaders but are also killed themselves, and one of the Colonial troops is almost killed by one of the alien warriors.
Alien Shooter 2 features several game modes, including Story, Classic, Multiplayer and Arena modes. The story mode involves an introduction of the plot and main characters. It gives an overall overview of the game and how the story develops and progresses. The Classic mode in Alien Shooter 2 features simplified controls and higher quality graphics, though it is generally the same game as the original Alien Shooter. The multiplayer mode in Alien Shooter 2 features two variations; versus PvP and versus PvE. The PvP game is an intense session in which two teams of up to four players fight head-to-head for the win; the objective is to eliminate all aliens before the time runs out. Finally, the Arena mode is another variation of the multiplayer mode; here, up to three players fight to see who has the most kills.