In a dead colony, a corporate marine is left far behind enemy lines. With an unlikely help of an insurgent drone, he faces the battle for survival against an army of murderous, mindless mutants... and worse things. Use the friendly drone for game-changing abilities. Survive waves, upgrade, and uncover the mystery in this cooperative, action-packed 2-player twin-stick shooter experience.

Go to: http://store.steampowered.com/ and download STEAM client Click "Install Steam" (from the upper right corner) Install and start application, login with your Account name and Password (create one if you don't have). Please follow these instructions to activate a new retail purchase on Steam: Launch Steam and log into your Steam account. Click the Games Menu. Choose Activate a Product on Steam... Follow the onscreen instructions to complete the process. After successful code verification go to the "MY GAMES" tab and start downloading.