The ray monster was a carnivorous creature that was housed by King Elbo in his Coral Castle. The beast was kept in an isolated pool, above which hung a large wooden crate. Intruders would sometimes be trapped in the wooden crate, and the ray monster would harass the prisoners by jumping from its pool and snapping at the crate, trying to get at those inside. When the Ewoks, Wicket Wystri Warrick, Kneesaa a Jari Kintaka, Latara, and Teebo were trapped in the crate, they accidentally increased the size of the monster due to a misplaced potion dropped by Teebo. The much larger monster was able to get at the crate much easier, and it threatened to devour both the crate and the Ewoks. However, the monster was stopped from doing so by Elbo at the last minute.