There are three spots where you can scare the wraithwing far enough north that the mimic might reach it.
×But at the west, if the mimic goes down that way, it can't get back to the third wraithwing.
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×In the center, the mimic can only get far enough south to move for the kill if the red door is still up, but it can only get to the one kill spot if the red door is down.
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×And at the east, there's no way to get the mimic far enough south, since you would need the mimic on one of the last two rows while you're on the top row.