Alpha Accident: Terra Nova

Alpha Accident: Terra Nova has not only new maps, textures and music but also new things. Also there are new monsters (boss included), and a new (barely) map hazard - voltage... Maps in this episode are quite large and more of an andventure sort than anything else, but there's enough monsters to shoot at.

Set on Mars during horrific events on it's moons another marine is stranded on old terraformation base, suddenly under attack by unknown force. During his journey he learns that there's something more serious going on than just UAC's genetic experiments...