Insane mode levels are exactly the same as the normal mode equivalent, but there are no checkpoints and if you die you will start from the beginning lose all of the items you are carrying. Remember that only three gems are required to activate the exit, and in a typical level at least three are simple to collect. The acid bubble can be extremely useful, as jumping on top of it it will provide you with an extra jump. It is often possible to skip puzzles and even sections of levels by utilizing it. The dart gun has some situation use, when there's not enough room to use the bubble effectively. Replaying normal levels to get an A++ rank is a good way to practice and earn some gems at the same time. If a secret level is activated and then completed, the story level that contained it will count as completed.