I tried specializing all my points into a single spell tree and then tested them on the same couple of levels. I learned that the Ice is MUCH more powerful than the other two. This may just be my play-style, but ice was way OP.
A final objective might make it more interesting for a 5 minute game. Also, you might want to inflate the cost of the sps items to make it exponential rather than linear. (typical ideal game suggestions) Good luck!
 "Minimalistic House Escape 5"){kind=icon}
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