Glacial Deep

The Glacial Deep is an underground cavern buried inside a giant glacier. Its ceiling and walls are formed by an incredibly dense layer of ice thicker than most trees are tall; this thick ice layer insulates the chambers inside, which in turn suck down cool air and vent out heat. The Glacial Deep is thus kept freezing all year round. Despite its extreme temperature it's actually a far lively cave than most; streams of freshwater trickle down from the surface and dim but regular sunshine allow for plant and animal life. The stone caverns below are colder, darker, and much less hospital, but a few specialized monsters still make a living there by drinking from huge underground lakes and feeding on bits of carrion that tumble into the abyss.

Environments
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Native Monsters
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Real World Inspirations
The Glacial Deep draws inspiration from multiple real world biomes but is most heavily based on the glacial ice caves of Iceland.