As MarkkuTuovinen mentioned it should have autofire, it kinda puts a bit of a strain on your hand when you have to click everytime you shoot.
Good game especially with the 3 hour time frame, you should check out http://www.ludumdare.com/ it is a competition where you have to make a game in 48 hours.
It once spawned me inside of a house and I was unable to move, not big of a deal but I had to reload the page, and it's that kind of thing that makes people quit.
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 "Stick Street Fighter 2"){kind=icon}
 "A Bit of Fun"){kind=icon}