Now that a sufficient amount of time has passed, I'll include a demo for future reference.
A word of explanation (also contains hints if you're trying to attempt this challenge by yourself):
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×Killing the slayer here requires you to do three things. First is to alter the slayer's orientation, second is to trick him into standing still for a number of turns, and the third is actually killing him.
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×The first and second parts require the use of the open yellow door in the middle of the room, since it does not contain oremites. (The roach directly south of this open yellow door can pretty easily be manipulated back on the hot tile)
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×The third part requires you to heavily abuse obscure movement and turning rules around the left turn in the northeast corridor leading to the green door. I have yet to see this particular application in any other demo, but I might be wrong on that point.
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×As an extra (impossible?) challenge, I've yet to kill the slayer in a mirrored situation, but perhaps another person might have a bit more luck with that.
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Drod Number: 3034; 8th person to see the Second Sky