Endwalker Main Scenario Commentary & Feedback

[Theozilla]

This is where things get really wibbly-wobbly-timey-wimey but very simple if you have the right picture in mind.

Our "other self" from the Eighth Calamity timeline does not need to travel back in time at all, and in fact would confuse things for our side of the time divergence if they did. The time loop only happens on our side.

Although the starting point for our time travel trip is after the two timelines diverge, our destination is before the split. What we do there affects "the past of both timelines simultaneously" because they aren't separate things yet.

Therefore it is our presence in Elpis, and ours alone, that is experienced and remembered by the people there.

(Or to look at it another way, if our other self somehow did make it to Elpis prior to their untimely demise, they would be arriving in the same Elpis that we visited ourselves. There is no alternate version of those events.)

I think that’s an over-complicated way of viewing multiverse-theory time travel. It’s far simpler to assume that the 8th Umbral Calamity timeline is now a separate parallel timeline to the main one, instead of a diverging one. That way allows for the 8th Umbral Calamity timeline to differ from the main universe timeline both past and present, since causal loops require both to work.