“Future Trunks SAGA” Dragon Ball Super Episode 51 Black destroyed the Time Machine that Trunks used to travel to the past before being sucked back into the future by the portal. The young Saiyan was very sad because he could not return to the future to save his world from Black's evil. But Bulma had a way and that was the Time Machine that Cell used when he came to their world and she hid it to study. So Trunks once again had hope that he could save his world in the future against Black. Son Gok