Half of a pair, a black koi is either sable or obsidian with either a spot of either alabaster or platinum on its back. It is a natural predator, and a fierce, short-tempered defender of its teritory. Anything that eats a black koi becomes one unless they save vs WP 25, and if they succeed, they take on an aspect of either the Obsidian Obelisk or the Sable Night, depending on which color the koi was. If a black koi eats a white koi, both cease to exist.

Black Koi manifest: Yin, a pet of Tambala, Sable with Alabaster.