Goku, Vegeta and Future Trunks face off against Fusion Zamasu.
Goku and Vegeta fuse via Potara earrings to become Vegito, with the latter immediately engaging Fusion Zamasu in a fierce battle.
Future Trunks gathers energy from mortals across the world and destroys Fusion Zamasu's physical body.
Fusion Zamasu's remains merge with the fabric of reality itself, destroying all mortal life in the Twelve Universes of that timeline, and due to the threat of Zamasu's influence spilling out into other timelines, Goku summons Future Zen-Oh, who subsequently erases all of existence in that timeline, which he deemed beyond saving, finally ending the threat of the Zero Mortals Plan and the terror it created.
Future Zen-Oh is transported to the main timeline's past by Goku and Future Trunks through the Time Machine, leaving this timeline empty, bringing it's history to an end.