Another bug/easter egg: in level 11, jump over the roof to the right and on top of the cliff. Jump into the new area, and you will be on the roof of one of the areas except it will be bugged. Jump further right to get to the final area, also bugged. Jump further right to get to some fragments of brick.
I think the easiest way to get 7000 meters is to shoot at an angle 30 or below, use a Freaky when you hit the water, then use all 3 Thrusts. I didn't have full power and got 7830 meters. Also, PYLemire's guide helped me, but on level 3 it's much better to get 2 Thrusts and 1 Ski.
Mobs are automatically banished back to the start location when they get to the exit. Click the mobs to find how much they cost to banish. You can't do it manually.
Wakahoola: Get many towers with lv.3 gems over few towers with higher level gems (though at one point you need to upgrade). And you should save up mana for one banish.
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