3 years after the events of MKX a great war breaks out between Outworld and the Netherrealm. The prize- the lost nation of Edenia. Kitana wants to reclaim it and merge it with the Netherrealm but Kotal Kahn is insistent on keeping his kingdom whole.

As the war drags on, Outworld is becoming weakened, many of Kotal's allies and henchmen have either died or betrayed him. Instead of seeking Raiden's help, he goes to Earthrealm in search of a relic that he once possessed and wielded back when the Aztecs worshipped him as Buluc.

The Crystal Skull of Azatlan would increase his powers and allow him to personally kill the Dark Emperors Liu Kang and Kitana.

However, when he gets to Earthrealm, he is being watched-

https://www.youtube.com/watch?v=Ap3bQH-yeKk

Now in the possession of the Special Forces, the Crystal Skull's inherent magic seeps it's way into Special Forces computer banks.

Meanwhile Raiden rallies Special Forces to join him, The Lin Kuei and The Shirai Ryu in Outworld, he has relented and decided to aide Kotal Kahn in pushing the invaders back to the Netherrealm.

Cassie & Friends teleport to Outworld, but the one they find themselves in is completely different.

Soon they learn that they are indeed in Outworld... Outworld 25 years in the past. Shao Kahn is still ruler and the Original Earthrealm Heroes are all still alive.

The SF kids hatch a scheme to change past events and prevent future events, they vow to work as a 3rd party and protect their predecessors from death while hiding their identities...however, the butterfly effect can still wreak havoc... altering events can have consequences, hidden dangers will be provoked and not everybody in Cassie Cage's team will return to the future alive. The Fire Rises and an ancient evil is waiting in the wings.