Not bad.
As others have posted, there should really be a warning about level 18 that you need insta-kills. The only reason I got through is because I went soul/move my first game and couldn't kill squat, so all my money went to insta-kills.
My second playthrough I did defense/soul, with a bit of attack. It would have been nice if I could click once on an enemy to kill it when it was doing no damage to me and I was only doing a couple of points of damage. It got very tedious killing enemies by clicking on them forty times (hence, the bit of attack, from extra level ups).
Controls are rather clunky, especially window control. Arrow keys also move; using them plus left hand for skills/buttons is more intuitive. Graphics are neat, system seems solid enough. 3/5.
Not a bad game, but way too short.
For those who are having trouble with the later levels: it's not always bad to hit red blocks, though they deduct from your score if they fall. Think about how they'll move, and see if you can use them to move more green ones.
Also, a lighter touch is sometimes better.
Finally... keep your mouse over the next button; if you're in a situation where a bunch of red blocks are about to fall in, but you have enough points to get to the next level, you can click it to move on before they fall in.
There's a bug when you just miss a ring, none of the other hoops will register, even if you go straight through them. It's really annoying on the Hoops stages.
I have to agree with everyone, the Insane levels aren't difficult at all, you just have to keep trying until you get lucky. On the other hand, the Easy/Medium/Hard levels were more fun because there was strategy to where you would put your points.
For Schism, make a cloud in the middle, jump over and hit the right switch, jump in the middle and make a cloud in the middle, float up and hit the switch on the left, jump in the middle and blow everything you have downward to make a path to one of the exits.
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