Originally Posted by
Endus
There's no problem with two Thanoses. We see what, like 10 Lokis in the same room, in the Loki show? Variants can hang with variants if they can hop universes, no problem.
And yeah; the "future" of Thanos2 after he jumped to Timeline1 for Endgame? That would've gotten pruned, because that's not the Sacred Timeline. Same for the future of Timeline1 that existed before Thanos2 jumped in to change it; pruned. The only future that existed required a Thanos2 jumping in to change that future path for the Sacred Timeline, which is the only reason the TVA would've let it happen.
Frankly, and I know we're agreeing here so this isn't directed at you, this is the whole reason the Loki show gives us the Infinity Stones serving as paperweights in the TVA. Because the TVA is so totally capable of pruning a naughty Infinity Stone manipulation that they're drowning in the things and don't consider them dangerous, at all. They wouldn't have a problem with Thanos and an Infinity Gauntlet. That's the point. He's not breaking anything the TVA wants; Thanos2 is a necessary component of the Sacred Timeline.
Notably, the agents of the TVA have the necessary perspective and thousands of years of practice at jumping timestreams and manipulating them. Both Banner and the Ancient One don't, and have a limited perspective from within a single timeline. Necessarily, because the TVA are pruning everything else. That's what Strange doesn't understand, clearly, about the timeline, and which the Ancient One couldn't communicate because she didn't understand it; you can look at possible futures, but there's only one real future. Strange honestly didn't have to worry about the one way to victory in a million possible futures; the TVA were guaranteeing that future would be the one that came true. All those other options he explored were universes that would be pruned if they came to be, and some Strange, somewhere/when, would make the right choices and that'd be the only future that ended up existing. If Strange had really understood that, he would've reacted differently; the TVA are essentially serving as "God's will" in symbolic terms. Whatever you do can't be "wrong", because if it's "wrong", it gets pruned, and only the versions who make the "right" decision actually end up existing.
Of course, "God" here is just Kang, who's fallible, but it was impossible for Strange to screw up and not get things right. The TVA would've made sure he didn't. At least, where "he" was "the only version of Strange that existed at the time", rather than however many got it wrong and got pruned.
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See the MS Paint graphic I slapped together a few posts back.
Both Thanos timelines are, simultaneously, the "sacred timeline". Thanos2 is only tolerated long enough to port back into Timeline1 for Endgame; it's a branch that merges back into the main. And the only future that exists is the post-Endgame future, neither Thanos2's hypothetical future had he not gone to Timeline 1 nor the future of Timeline1 without Thanos 2 would exist; those aren't the Sacred Timeline, and thus they'd get pruned.
The events of every Marvel film are still the canon of the Sacred Timeline up through to the end of Loki. Nothing in Endgame changes that. It just added some time travel notes that we didn't get to see the first time around, but which didn't change anything significant. You may as well assume those time travel events always happened, even in the films we watched, they're just off-screen.
The one exception being Loki grabbing the Tesseract and booking it; that's a variant and that timeline was pruned (though that Loki survived). That didn't happen in the Sacred Timeline, but it took us seeing the Loki show to realize that. In theory, if any of that time travel did create a deviation, it would've gotten pruned, too, but we literally aren't shown anything other than a TVA agent stating outright that the Avengers time travel was fine and didn't break anything.