"X front" than to the Earth is alien infection background story, players play a biological robot, in order to restore infected the Earth, but with alien creatures to fight. Game game presented in the form of checkpoints, each level will require players to operate a robot to deal with four central attacking monsters. Click the button corresponding to the direction and shoot the enemy to attack, when to defeat all incoming enemies, levels can be passed. In the clearance process, you can also upgrade the characters, and guns to be strengthened.