Pretty cool game. I know there are other runner games, but Canabalt comes to mind first. This doesn't match it in style or atmosphere, but definitely gains points for its variety.
The mercy is interesting. It separates the games quite a bit. For some, this would be more fun because it'll let you get away with small slip-ups (still without babying you). For me, the mercy also makes it less intense, and less exciting.
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