My reasoning for ruling that out is that, technically, Future Trunks' timeline should branch off after he first returns from giving Goku the heart medicine in a timeline altered by Cell. Whatever changes he's encountered at that point would just be the minute butterfly-effect differences due to Cell's presence, but in the strictest sense, that should count.Zephyr wrote:though in another thread last night I concluded that his last time looking in the box could have been "after" (in the "meta in-universe chronological" sense) Trunks and Cell had created the (going by my naming scheme) Movie 7 Timeline and the Cell Games and Black Timeline, respectively, and he must have put it away "before" (again, in the same "meta in-universe chronological" sense) Trunks created Trunks' Timeline.
Then again, they threw that out the window by attributing this latest splinter to Beerus rather than Trunks, so I guess only the "big" changes count. It doesn't make any sense -- wouldn't people having even the most minutely different memories of events require two parallel timelines? -- but oh well.
To add to Zephyr's explanation, you just need to break down the causality for each split. Both those timelines splinter from Cell's. Starting from Cell's timeline, you have:ChiefWamsutta wrote:Why wouldn't the Goku Black Timeline branch off of the Future Trunks Timeline?
1) The "unseen" timeline (or Zephyr's Movie 7), altered only by Trunks.
2) Black's timeline, altered by Cell (but also set to have Trunks arrive in it as part of its events).
3) Trunks' "good" future, which is also the result of his past being altered by Cell; Trunks has different experiences in the past than he would without Cell's presence, and is able to prevent his own death as a result.
4) The main timeline, altered by Cell, Trunks, and Trunks again after encountering Black, splitting off from Black's due to Black's origins being prevented.
But yeah; Cell indirectly causes both Black's timeline and Trunks' "good one" (or not-so-good, as of this arc). Just as Trunks delivering the heart medicine leads to two outcomes for Goku--one in which he dies, and one in which he survives--so too does Cell interfering with Trunks' personal past lead to two scenarios for Trunks. The fact that that interference happens during a time when both of them have traveled to the literal past is immaterial.
Basically, the Trunks Cell kills has a past that involves spending time in Age 767. If Cell goes back to Age 767 at that point and enacts further changes, he's altering Trunks' personal history as well.
Trunks' timeline doesn't diverge from Cell's until after he returns from his experiences in the new version of the past. The "Future Trunks" timeline is, in fact, the "last" to be created during the events of the manga. It's the last splinter.


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