Eel

“Eels are long, snake-like, ray-finned fish that are primarily nocturnal. They have a keen sense of smell and can be harmful to humans due to their strong jaws with shark-like teeth. Some eels also contain toxins that can destroy red blood cells. Eels move in an interesting way due to their lack of pelvic or pectoral fins. To swim, eels generate waves that travel the length of their body, making them resemble snakes.”— in-game Bestiary description