This game isn't hard at all. None of the puzzles requires real thinking. The only hard thing is the bad physics engine you've got to cope with and the fact that there are sometimes too much items to properly move them around with a bad engine.
And why the heck put in a time limit? That has nothing to do with the type of game it is, as you can just replay levels, and your time doesn't show your puzzle skill but merely how good you can cope with the engine.
This game could have been much better with some more good thought about it.
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