sorry for double post here is his background
Scorpion's chronological first appearance is in Mortal Kombat Mythologies: Sub-Zero, where Quan Chi had hired him to find a map, in case Sub-Zero failed. At the time, Scorpion was an assassin for the Shirai Ryu, and his name was Hanzo Hasashi. The Shirai Ryu was a single clan out of the many connected clans through Japan known as the Ninja. The Shirai Ryu were started by a renegade Lin Kuei member named Takeda who seceded from them, and the Shirai Ryu was the very clan he started. This made the Shirai Ryu a fierce rival to the Lin Kuei. When the two met, they battled until Sub-Zero defeated and decapitated him. Scorpion returned to fight Sub-Zero in the Netherealm as a vengeful spectre, but Sub-Zero escaped him. The two met for the penultimate time on Shang Tsung's boat, where Scorpion told him he would kill him in the Mortal Kombat tournament, which he did.
Scorpion followed Sub-Zero, apparently alive again, when Shao Kahn hosted Mortal Kombat in Outworld. It is unclear whether or not they met, but while watching one of Sub-Zero's battles, Scorpion witnessed this Sub-Zero sparing the life of his opponent. From there, he grew confused and did not fully understand why the Lin Kuei warrior had grown so merciful. He would later on learn that this Sub-Zero was not the same man who murdered him so many years ago and that it was actually his younger brother, sent as a replacement. As a result, Scorpion vowed to become Sub-Zero's protector as his way of apologizing for the murder Sub-Zero's older brother.
When Shao Kahn invaded Earthrealm and unsuccessfully tried to conquer the Netherealm as well, Scorpion was set free. The emperor enlisted him in his extermination squads. However when Scorpion discovered that Sub-Zero was one of Earth's warriors, he turned on the Emperor. He took part in helping Liu Kang in the final showdown with Shao Kahn. When Earth reverted back to normal, Scorpion was driven back to hell, only knowing that he will one day rise and walk the grounds of Earth once more.
During the events of Mortal Kombat Gold, Scorpion was released again by Quan Chi. In exchange for life, Scorpion would fight Sub-Zero (Quan Chi had told Scorpion that Sub-Zero was the true murderer of his family and clan). He eagerly accepted, but was shocked to learn from his former nemesis that it had in fact been Quan Chi who had arranged for the killing of the Shirai Ryu and Scorpion's family. Enraged, Scorpion leapt at Quan Chi and the two landed in the Netherealm through a dimensional gateway.
For the years that Quan Chi spent in the Netherealm, he would be chased, brutalized and tortured by Scorpion. Quan Chi had little chance of escape, as his powers would be weakened while he was in the Netherealm and Scorpion's power and strength increased while in that realm (note: Quan Chi, as Shinnok's second-in-command, had previously resided in the Netherealm. However, this was explained as a new region of the Netherealm where sorcerors lose power). Quan Chi had struck a deal with the Oni Drahmin and Moloch, who fought off Scorpion for him. When Quan Chi escaped the Netherealm though a portal, Scorpion followed him, but the volatile portal did not send him to the same place. He continued to hound Quan Chi in a hide-and-seek game for the years to come, until Drahmin and Moloch threw him into the soulnado, scattering his essence across the realms.
While it was believed that Scorpion was torn apart by the souls in the Soulnado, he really wasn't. He actually managed to ascend up to the heavens where the soulnado emerged from and from there was he able to avoid death. From there, he would witness the Elder Gods, in whom he had never believed. From there onwards would he be changed from what he saw. He also witnessed the supposed death of Raiden and the dominance of the Dragon King being to unfold. The Elder Gods were aware of his presence and enhanced his mortal and special abilities. He was given a special task by the Elders to kill Onaga. Accepting this new mission, Scorpion emerged to Outworld once more in search of Onaga. Now it is the hell spawned spectre who is the true champion of the Elder Gods.