Unlimited health, ammo.
Your aim in this great shooting game is to survive enemy attacks for as long as you can. There are several game modes. In practice mode, you can check out all of the weapons without being attacked. You can also obliterate a stuffed Thing-Thing target! Be sure to collect all power-ups, as they will help you to sweep more enemies.
Use "A", "D" KEYS to move left and right, press "W" KEY to jump, hold "SHIFT" KEY to run. For double-jump press "W" KEY in mid-air. To perform a backflip (helps you to dodge bullets) press "W" KEY while moving backwards. Press "E" KEY to change weapons. And use YOUR MOUSE to aim and shoot. Good luck!