My ideas for a future version are:
WASD to move the plane
and mouse to control the gunning.
The only reason I didn't put more stuff in was due to time constraints, and I go to school as well which is a bit hectic.
@jingks - buy upgrades!!
Both seem too similar - CHEAT ALERT
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Your numbers are incredibles, you are powerful.....congratulations...... excellent game..... This is not cheat, this is great game......
This game is show!!!!! congratulations!!!!! You are winner!!!!!