Raptors are reptilian humanoid beings that evolved from the dinosaurs, millions of years ago. They once thrived in Earthrealm. However, they fled to the realm of Zaterra during the war between the Elder Gods, Raiden, and Shinnok. Eventually, Shao Kahn would invade the realm of Zaterra and merge it with Outworld. It is unclear as to why, but the Raptor race was almost driven to extinction while in Outworld. Reptile and Khameleon are the only two confirmed survivors. Chameleon is also believed by many to be of Raptor descent as he shares many of the characteristics of Khameleon, such as the ability to change colors.

Another interesting characteristic of Raptors is that they appear to de-evolve the longer they are away from others of their kind. Reptile's appearance has always been more humanoid in earlier Mortal Kombat games. However, in Mortal Kombat: Deadly Alliance, his appearance seemed to be much more reptilian-like, even developing a tail. Although, once Khameleon resurfaced in Mortal Kombat: Armageddon, he lost the tail and his body appeared more humanoid, again.