Super Street Fighter II: Turbo introduced Akuma to the series, who is known in Japan as Gouki. He is a ruthless warrior hellbent on using the fighting style of Ansatsuken Karate for its original purpose: death matches. By doing this, he has allowed his humanity to be corrupted by the killing intent of the Satsui no Hado. It is the same dark, enslaving energy that manifests itself within all Ansatsuken practitioners who become strong enough to feel its influence.
It is this evil power that allows for the usage of Ansatsuken’s most dangerous and most lethal technique…the Shun Goku Satsu.