Couple balance issues. Never buy a bow, because the second-best bow will always drop in the level. Never upgrade your bow, since you'll always get a new one. In the store right after you kill a boss, spend everything you have on healing potions, since the price is about to go up. Spending money on arrows is okay since you get 100, but they drop too.
Why do the health potions get more expensive? Not a lot of money in the game, and no auto healing between levels. Spending all your money on what should be free is crappy.
Powerups are erratic and overpowered. Sometimes touching them gives you nothing. But when you get wings it breaks all the jumping and fan levels, and when you get heart arrows it breaks all the fighting levels.
If you have a red ball in the lowest row, a green ball above it, and a green fireball in the cannon, you lose. The fireball should go through the red in to the green.
If you use the first level spell after filling the bar all the way up it should only take that portion of the bar away. Killing nearby or diagonally is retarded with kill all lit. Either disable them or make them useful by using less magic.
Very interesting, but you occasionally clip right through walls. If you hit an edge with your hip, it should stop you instead of loking like a bug that you don't land right. I think a drop shadow on the character would be helpful for sticking long and short jumps. And get rid of the butt-splat frame of animation! There is one frame after landing that you can't jump from. It is so annoying to watch him bounce right off a ledge that he lands on the far edge of.
The vertical speed gimmick is awesome. But the "carpal tunnel equals damage" thing is just poorly conceived. Wiggling the mouse is bad for you, kids. Don't do drugs.
Needs a tooltip for what the add-on weapons do in the elite shop. The 75K "Plasma Bolt" one sucks. It makes little red dots spin around you, but with the generous ship collision circle it means you'll crash in to something to use them.
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