The Abyssal Library

The Abyssal Library is one of The Nine Great Libraries. Its primary function is to record the exact dimensions of the universe, and the expanding volume of the void. However, this library also keeps records of dark and abyssal planes and watery dimensions unseen by mortal eyes. The Abyssal Library has the largest collection of books describing incomprehensible creatures, primarily those that swim through the primordial aether beneath reality.