Quick recap
The future Trunks comes from. Goku died of a heart disease, and Androids 17 and 18 killed Vegeta, Piccolo, Krillin and the rest. Thirteen years later, only Gohan, now an adult missing an arm, and the teenage Trunks remain, and Gohan trains him while the androids destroy cities for fun. Gohan heads out alone for one last fight and is killed. Finding his mentor's body, Trunks goes Super Saiyan in rage but still loses to the androids. Bulma finishes the time machine, and Trunks leaves for the past to warn Goku and deliver the medicine, determined to come back stronger and end the nightmare.
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