The UAC science ship H.M.S Explorer is orbiting earth, Demons from Mars Base have come through the on board teleport, and killed everyone on board the H.M.S Explorer, the ship is on aux power and will shut down very soon. You are a marine sent from Mars to stop the Monsters from reaching earth. "Kill the Cyberdemon and get out of there!" are your orders, find the escape pod as the ship will soon shut down and crash into the Moon.
This is my first decent map that i have made, this is alot better than Zombie Attack: Episode 1 as played by pieceofpiesoftware on You Tube. I will remember to keep a backup of the .WAD so i don't loose it, Megaupload was shut down and i lost Zombie Attack as the map wasn't on my PC after i uploaded it. Hope you enjoy this map as i put a lot of work into it, i had to make a whole new map as the previous one got corrupted or something.