The Chomposaur is an enemy in EarthBound. It looks like a purple cross between a Stegosaurus and a Brachiosaurus. It can use PSI Fire in its α, β, and γ levels, swing its tail very hard, and stomp with its huge foot, and enters battle with a Shield α. It is weak to PSI Freeze, and drops a Magic fry pan, the ultimate weapon for Paula, 1/128 of the time upon defeat.

Early Concept Art

Lost Underworld Concept

In the Mother 1+2 Art Book, early concept art of a Chomposaur and Wetnosaur in the Lost Underworld shows that the Chomposaur changed little from its original design.