Name: Chameleon
Origin: Outworld
Race: Clone of Various Races
Playable Debut: Mortal Kombat Trilogy (PSX, PC, Saturn with code)
Unplayable Debut: Mortal Kombat Trilogy (PSX, PC, Saturn)
Story: Fearing the same result would come about during his invasion as in all the Mortal Kombat Tournaments, Shao Kahn had Shang Tsung implement a failsafe to ensure victory. Tsung and his group of magicians had plans for such a failsafe long before.
Tsung had one of the Outworld warriors gather the blood shed by Scorpion, the Sub-Zeros, Smoke and Rain. He also took the blood with consent from Reptile and Ermac. Shang Tsung even struck a deal with Noob Saibot for some of his blood for the knowledge he needed effectively for Shinnok back in the Netherealm.
Using the same methods that created Mileena, Tsung had all the blood samples combined and grown into one being through the use of science and magic. The science had granted the creation human form, but the magic had granted him the uncontrollable ability to shift from one of his "donors" to the other in a random form, gaining the powers of whoever he transforms into, thus given the name Chameleon.
However, the one thing that remains constant is his programming to stop the Earth warriors at all costs, even his own demise.
But, Tsung has the habit of keeping secrets from his allies.
Due to Chameleon's unstable transitions between powers and identities, the genetic structure of Chameleon himself is slowly breaking down until there would be nothing left of him but a puddle of genetic goo. This is known as the degeneration process, a process that plagues all clones eventually, and which resulted in Mileena's disfigurement.
Chameleon entered the tournament and began to fight through the Earth forces like they were nothing. He was there up to the final attack against Shao Kahn. When Kahn was defeated and Earth returned to normal, Chameleon had somehow disappeared. If he had been killed or simply degenerated into nothing more than a pile of goo will never be known...
Until maybe the next tournament.