good luck listening to Shadowassassin! you're supposed to ignor the uber shotgun, and go for the uber jetblaster, which will fire a bolt right at Chuck Norris....down below, blowing him up, and effectivly winning the level!
Some one help! I'm stuck at the part where CHuck Norris is on your team, but wont use any smarts to save you from being squished by two giant mr potato heads!