The Gumberoo (Megalogaster repercussus) is a fearsome critter told by the lumberjacks of emerging America in the 19th and early 20th centuries.
The Gumberoo is said to look like a fat bear in shape but completely hairless except for its prominent eyebrows and bristly hairs on its chin. Instead it has dark, smooth, and extremely tough leather-like skin. This makes the beast invulnerable to bullets and arrows.
Anything shot at the beast, simply bounced off. Its weakness was fire and was the only known way to defeat it.
Gumberoo was also said to always be hungry and devoured anything it can find that looked like food. A whole horse may be eaten at one sitting, but it's not enough.
Gumberoos make their dens in the bases of huge, burned-out cedar trees. The creature spends most of its time in a state of hibernation, only leaving its lair a few times a year to search for food. When active, the gumberoo is always hungry and will eat any living creature that crosses its path.
The first confirmed kill of a gumberoo by an M-Force agent occurred in 1957, when Mike Mulligan and Abernathy Quinn destroyed a gumberoo near Coos Bay, Oregon. There have been numerous reports of gumberoos since then, but only five confirmed sightings and no successful kills.