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 Bogeyman appearance conditions
My experience playing adventure mode in 43.05 is that bogeymen haven't appeared most nights I've slept outside or travelled after dark. At first I thought that it was because the "sleeping inside a circle of campfires" trick from previous versions was working. Then one night a group of bogeymen appeared despite my campfires, jumped into the middle of the circle with me via a tree, and killed me.
The night this happened was the new moon, so my tentative theory is that bogeymen only come out on moonless nights. I haven't played through enough in-game days to get to another new moon yet, but I have slept outside, completely unprotected, while the moon was up without any bogeymen appearing.