Ventricle Coral
Ventricle is a species of coral native to the Kajh-Tai Region. As it grows, it hollows out, transferring material from its core to its outer shell and leaving a massive Corralum behind. Many other speces rely on this hollow to live in in the otherwise arid Kajhtaioan climate.
Arched furrows which form natural channels and tunnels for the collection of humidity and dispensation of rainwater.
Where it breaks, it regrows, forming creases and overlaps that give us a picture of how Jhoutai's underlying tectonics have shifted over time.
Are they big enough for a person to live in? (Not saying it's a good idea, but... seems cosy.)
One of the largest is the Yak'koli ventricle, which is over 3km from roof to floor! There are smaller ones, though. You want to make sure you're not sharing the space with anything, but they're good cover from the sun for sure.
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