Deep One

The Deep Ones are a species of aquatic humanoids with both fish and Anurid characteristics (simply put, frog-fish men), dwelling in cities at the oceans bottom. These creatures were first introduced in the H. P. Lovecraft story The Shadow over Innsmouth, and revere both Mother Hydra and Father Dagon. Deep ones, despite their preferred marine environment, can survive on land for extended periods. Deep ones are capable of Hybridizing with Humans, resulting in a person with the "Innsmouth look", which will eventually metamorphose into a complete deep one and return to the sea. Deep ones can also hybridize with the Yuggs, sentient flatworms.