Mathayus is the Akkadian warrior that was well known as the Scorpion King among all that knew his identity, and would become an ancient evil that was stopped from decimating the Earth by Rick O'Connell.
He serves as the tertiary antagonist/tragic villain in the 2001 film The Mummy Returns and is portrayed by Dwayne Johnson (although the character becomes totally animated during the climax of the film).
The Last Akkadian
Mathayus, along with his two brothers, the last of a dying people, the Akkadians, Mathayus became a mercenary, training extensively in the deadly arts and only applying service to those whom he and his brothers personally favoured, though upon the death of his brothers, Mathayus went on to end the reign of Memnon, a murderous warlord who sought to conquer all around him, and went on to become a warlord himself known as the Scorpion King. Upon Memnon's death, Mathayus ascended power by assuming the role of a king, becoming a formidable ruler in ancient Egyptian times, before the era of the Pyramids.
One siege on the city of Thebes was the final battle that the monarch and his men fought as they were forced out into the deserts where Mathayus earned the favour of Anubis himself and returned to decimate Thebes, losing his soul once the battle ended so that he was condemned to return to the oasis that had been given him by Anubis, awaiting a challenger in a hibernation-like stasis and under a severe transformation that caused Mathayus to lose his humanity.
Return and Death
Five thousand years on, Mathayus remained in his state until he met the resurrected High Priest Imhotep and the adventurer Rick O'Connell, both of whom sought Mathayus' destruction, but only Rick achieved it, sending the warlord and his forces back to the Underworld.