Gargos is an ancient creature spawned from the Astral Plane. Sadistic, vain and utterly megalomaniacal, this nightmarish entity rampaged across his own dimension, killing all who opposed him and siphoning their powers, eventually becoming the supreme Shadow Lord—a master of Shadow Energy.
For thousands of years Gargos has attempted to take over other worlds, including the Earth; but he was always thwarted by the benevolent Astral beings known as Ichoriens. These demigods sent Astral Spirits to aid humans in their battles against Gargos; and sometimes gave Astral powers to human warriors, like the immortal Barbarian called Tusk.
Gargos finally vanquished the once mighty Ichoriens; and the last good Astral denizens—the Guardians—fled that plane, escaping to other dimensions. They sealed off the Astral Plane behind them so that Gargos could never taint another world with his corruption.
But then Gargos used his telepathic abilities to manipulate an Earthling—the nefarious sorcerer Kan-Ra—into reopening the gateway between the two worlds. Now the Shadow Lord is bent on spreading his corruption across the globe, and turning humans into his slaves forever.