The Forest Devil was a beast created on Caput Tatiium over 35,000 years ago when the Celestial Bison decided to hide his Shadow Magic abilities before his death. He thought that a living Shadow Artifact was the last thing anyone would expect, so he let his abilities manifest as a living creature, creating the Forest Devil. The beast was a man-eater, and the Celestial Bison was its first victim. The Forest Devil then took residence in a nearby cave near Possopia, the capital of the Possissippian Civilization living there at the time. The Forest Devil would prey upon anybody or any animal unfortunate enough to travel near its cave. The people eventually became used to the cave and began outright avoiding it. This practice continued, even after the Possissippians split into the Possumwhatan and Chipmunkee Tribes around 16,000 years ago. Then, Geronimo, who was the current Man of Light And Shadow, went to the cave to see if the beast (which had faded into legend by then) was still alive if it even existed. Geronimo was killed during his run-in with the beast. After 16,000 more years, during Tate's oppressive rule of Caput Tatiium's peoples, Weasel and his friends sought the allegiance of the Possumwhatan Tribe. They offered their allegiance if Weasel slew the Forest Devil. After a long, hard-fought battle, Weasel slew the beast (though he almost perished doing so), with the Sword of Caliber absorbing its power (Weasel had no idea he had just absorbed another Shadow Artifact at the time).