Research suggests a Shellder's consciousness inhabits the dazzling red jewel at the end of Starbro's tail; it seems the Shellder can telepathically communicate with Starbro, but Starbro never seems to listen or respond to it if so.
Its tail has a Shellder firmly attached with a bite. People in ancient times imagined that Starbro were transformed from the reflections of stars that twinkled on gentle waves at night.