Arcane

Yeah, it's such a shame. If only we didn't get the second "flashforward" (lol) where we see future victor talk to Jayce, the story would have been very well weaved and explained without big plot holes:

1. Jayce goes to the future, some semblance of victor tells him to go back and to kill him to avoid this future.
2. He does that, however this triggers a massive war.
3. Jayce loses, and he realises as he takes the form of the dead future jayce, that whatever entity was controlling Victor, or whatever he became after losing his humanity tricked him. He accepts his fate since he willingly killed his friend, triggering the death of thousands. 10/10
4. The wild variable, Ekko, appears. Ekko seems to free Victor from the control the mind machine has on Victor/Revives the humanity inside of him.
5. In that moment, Jayce recognises that this is actually the Victor he knows and that there's still a chance, so he tries to convince Victor, now that he is free of his control/apathy.
6. Jayce succeeds. Victory! (lol).

That last scene really breaks this timeline and the only explanation is that Jayce was too far gone when future victor talked to him, so much that he ignored the advice, only to remember it when he already was on the mind-world and ekko did his move... Which can be valid but... we just saw jayce deconstruct his hammer and do some incredible physical feats, he didn't seem to be clouded when he talked to future Victor, but determined.

It pains me greatly that either from a lack of exposition or from some excess they fucked up a masterful story.