Tyranthraxus, also called the Possessing Spirit and the Flamed One, was a malign entity who stole control over the bodies of others to further its wicked goals. He was said to have been one of the Seven Lost Gods forced long ago to bow before Bane. Some sages have identified him as a type of yugoloth, though spells normally effective against such fiends have been shown to have no effect on him. All that is truly known is that Tyranthraxus was an extraplanar entity of unknown origin but apparently (according to the creature's own diary), a very weak example of his kind.