Here's how mine works.

Three years ago, Shinnok was defeated by Cassie Cage. Raiden purified the corrupted jinsei the fallen Elder god left behind. But that cost some side-effects in Raiden's personality.

Since that event, Outworld's new emperor, Kotal Kahn had a war with the thunder god, leading to a new Mortal Kombat tournament. Takeda and his father, Kenshi left to fight the Red Dragon, freeing the demigod Taven to help them fight Daegon.

Kung Jin entered the Netherrealm to reunite with Kung Lao so that he can bring him back.

Kotal Kahn hosted the tournament with Earthrealm, Outworld and the Netherrealm competing. Cassie and the others competed. There was also a mysterious fighter who entered as well. But was not in the tourney to fight for Earth or any of the others.

The mysterious fighter fought against only the Netherrealm's remaining revenants. After fighting, he forfeited taking Nightwolf's, Kabal's, Stryker's & Smoke's bodies with him so that he can cast a spell that can return them back to living mortals again and he vanished.

Cassie and the others followed him to figure out who he is. Learning that he was being spied on, he offered them to join him in going to the Netherrealm to fight the new emperor & empress. There were many demons for them to fight, but the stranger mysteriously uses his power to control time and allows Cassie and her crew to fight them, just to see how good they are.

This story needs to do something a little "Deadly Alliance" just for the Dragon King to return near the end. He won't be the final boss, just as a cameo.