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The Ravenous Bugblatter Beast of Traal is a vicious wild animal from the planet of Traal, known for its never-ending hunger and its mind-boggling stupidity. One of the main features of the Beast is that if you can't see it, it assumes it can't see you. Due to this it has been considered one of the least intelligent creatures in the Universe.

The Vogons "wouldn't even lift a finger" to save their own grandmothers from the Ravenous Bugblatter Beast of Traal. The best way to irritate a Vogon is "to feed his grandmother" to this creature.

After leaving the Restaurant at the End of the Universe, Arthur Dent, Ford Prefect, Trillian, Zaphod Beeblebrox and Marvin encounter a shape-shifting Haggunenon in a "carbon copy" form of a Ravenous Bugblatter Beast of Traal. Arthur and Ford hastily escape from the creature, and we later find out that Trillian, Zaphod and Marvin escaped when the Haggunenon shape-shifted into an escape capsule.