Why not stagger the Idling achievements? Like, instead of going from 12 hours/720 minutes to 24 hours/1440 minutes, move minutes to be in between? It's just ages, then 2 achievements at once...
Upgrades are useless if they don't actually upgrade you. And using all my XP to upgrade humans to the point where I get elves, then having to upgrade elves, not fun.
Needs a zero-th life. Seems a convention in most games, that when you have 1 life left, and you die, you still have one more shot at it. Rather than a GAME OVER.
Just a tiny bug, textual error on the Exiled Student's card, in the 3rd move description, if I remember right. 'If hits' doesn't really make sense? Well, not proper sense
Really does need a pause button to be more enjoyable. Don't really like to be sitting at my computer for an indefinite amount of time, while everything happens around me.
I know it's probably too hard to constantly calculate the trajectory, like off obstacles and what not, but could the trajectory line atleast change colour if the ball's going to hit one? At the moment it can get pretty confusing, especially level 2-4
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