In the Glowpod Fields, in the Mountains of Night... There is perpetual magical darkness. Normal light sources won't work to illuminate the space here. 5 ft tall blue pods sprout from the ground in these arid highlands, casting faint magical light out from them. If they are bonked into hard enough, the pods open, shedding more light.

Their parts can be harvested for magical ingredients, but they take many decades to mature, and are fiercely protected...

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I think that dark oval thing is made of stone, about 20 ft high, and emitting a foul smelling dark blue smoke...