Bio: It is believed that some time shortly after the dawn of humanity, Genghis was given great power by the Vishanti. In return for this power, Genghis agreed to summon together the greatest mystics in the world for a tournament to discover the Sorcerer Supreme. It cannot be proved he received his power in this way, no one has memory of that time and Genghis himself has long since lost his mind. His mind clears for one day every century to allow him to preside over a new contest. It is in this way that Doctor Strange became the Sorcerer Supreme.
Strange has sought assistance from Genghis on numerous occasions but seldom is he of any help. By gifting Strange with an ancient scroll purporting to contain a means to reach Eternity, Strange was instead stranded in the Netherworld of Eternal Doom. Later, Strange sought out the help of the Aged Genghis against Dormammu and Baron Mordo. Aside from his centennial duties, Genghis is of little use and is often a danger. Nevertheless he has long been cared for as a guest of Strange's Sanctum Sanctorum.
As well as being mentally fragile, Genghis is physically frail as well. No longer able to walk any distance Genghis levitates nearly all the time.