Sonya is the acting general of the Earthrealm's special forces. After Shinnok's defeat, she became romantically involved with Johnny Cage and had a daughter. Cassie Cage.
She would lead an assault on Liu Kang's domains alongside Raiden, Johnny, and Cassie. While fighting, she would become entrapped in the crumbling castle and detonate planted explosives to destroy the army of the Netherrealm.
Kronika would then bring a younger version of Sonya into the present and a younger version of Johnny and Jax.