Alright...Just a basic tip, keep your mouse speed at maximum if you can. I'm not sure how it might work on other systems, but for me, I go to my control panel, go to printers and other hardware, and the raise my mouse speed up to maximum. It should help, at least a little. Of course, some of you are far beyond that.
Alright...For level 4, the one with two rows of cannons, it's best to use circular movements with your mouse that take up the entire screen. Time your circles right, so that when you're at the top, the cannons on the bottom are firing, and when you're at the bottom, the cannons on the top are firing. This technique isn't foolproof, so keep a weary eye.
Alright...For level 3, the one with the "Smashers" and one row of cannons, it's best to alternate from the very bottom left corner, next to the very bottom left "Smasher", and the near very bottom right, next to the second to bottommost "Smasher". Time it right so that you can move just as the Smashers tremble and the cannonballs are fired your way. Move quickly.
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