Rainbow Fish Grendel
From Creatures Wikia
The Rainbow Fish Grendels are another genetic grendel breed by Grendel Man. They look a little like Sea Monsters, and are expressive like the Sea Monsters, but are different from them in terms of living places. They cannot breathe on land. They need to live in the sea, otherwise they will die. An unmodified, stand alone Docking Station world will not suit them! Aquanornia works well, but any underwater room with sufficient food supplies will do for them. Also, they get crowded rather easily. It is best to keep them alone. They use the sprites of Mask Grendels and Maraquan Grendels.