Born Hanzo Hasashi, Scorpion was one of the finest shinobi from the Shirai Ryu ninja clan. His father forbid him from joining the clan when he was young, but Scorpion did so in spite of his father's wishes, because apparently there's good money in being a deadly ninja assassin.
Flash forward a few years and the infamous necromancer of the Netherrealm, Quan Chi, hires Scorpion to steal the sacred Map of Elements from the same Shaolin Temple where Sub Zero happened to be setting up shop. Sub Zero stopped Scorpion from stealing the map, and killed him in combat, but to avoid being similarly murdered by Sub Zero and his clan, Quan Chi offered them a peace offering: in exchange for not slicing his head off, he would send some of his goons to slaughter Scorpion's whole family, including every member of the Shirai Ryu.
Scorpion's soul found itself mightily peed off in the Netherrealm , where he was resurrected as a hellish ninja skeleton, vowing to forever make Sub Zero eat it at every opportunity. He's not evil. Far from it; he's just a wee bit upset over his innocent family and friends were slaughtered by a double-crossing d-bag.
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