Staryu is a golden-brown echinoderm Pokémon with five appendages that surround an exterior organ called the core, which resembles a golden metal casing with a red gem in the center and is held in place by a golden ring looped around its lower left point. If any of Staryu's appendages are lost or eaten by predators like Lumineon, it remains unharmed and can grow them back easily as long as the core is intact. When the sun goes down, the core glows brightest, and many Staryus will float to the surface and align themselves with stars in the night sky. In anime, if Staryu becomes weak, its core will dim and flash slowly. During summer ends, groups of Staryu tend to gather while lighting up in a steady rhythm. Staryu can be found at the bottom of the ocean on seafloors, but it has also been seen in rivers that lead into the ocean, as shown in Pokémon Snap. Camouflage was its signature move in Generation III. According to Pocket Monsters Encyclopedia and the original Japanese version of The Water Flowers of Cerulean City episode (EP007), Staryu is hermaphroditic.