Cetus

Appearance
A large sea monster. Its head is a Greyhound, and its body is a whale with a tail similar to a handheld fan.

Myths
The Queen Cassiopeia said that she and her daughter, named Andromeda, were far more gorgeous than the Nereid sea nymphs, and Poseidon sent Cetus out to get them. The oracle said that if they sacrificed Andromeda to Cetus they would be saved. They then chained her to a rock for Cetus to find, but later found Perseus managed to slay Cetus and took Andromeda for his bride.