Khameleon made her debut as a secret character in the Nintendo 64 version of Mortal Kombat Trilogy, while the PC, PlayStation, and Sega Saturn versions instead had Chameleon, a similar male character. After being absent for a long time she made her return in the Nintendo Wii version of Mortal Kombat: Armageddon with a new design.
Khameleon's biography and endings screens in Mortal Kombat Trilogy describe her as the last female of her race, as Reptile is the last male. They reveal that her race, the Saurians, also known as Raptors, were originally from Earthrealm, but a great war drove some of them out of that realm and killed the rest. They found a new home in another realm, which they called Zaterra or "New Earth." However, Shao Kahn eventually found it, and after defeating them in Mortal Kombat, he drove the Raptors to near extinction and then merged the realm with Outworld.
It is said that Khameleon spent an indefinite amount of time trying to find Reptile in an attempt to restore their race, although he remained unaware of her, focusing on serving Shao Kahn. Khameleon finally caught up to Reptile and told him the truth of how Kahn was responsible for the extinction of their race. However, Reptile fell under the emperor's influence once again and turned against her. Having failed in her attempts to slay Shao Kahn, she began to wander the realms contemplating a way to strike back at him. Later, during the events of Mortal Kombat: Armageddon, she learned of the battle that would occur in Edenia and the gift of ultimate power that would be granted to the victor. Distressed by the fact that Kahn was also seeking this power, Khameleon sought out to attain it for herself so as to exact revenge on him and his followers for what he did to her race.
Her Armageddon ending states that after defeating Blaze and gaining god-like power, Khameleon focuses on Shao Kahn. Although Kahn pleads for his life, Khameleon transforms him and his army into Raptors as an act of revenge for the death of her species. However, she also loses control of her powers and accidentally transforms the heroes into Raptors as well. Even so, this act restores Zaterra to its former glory.