Not that this manga hasn't gotten a touch odd but some of you are getting a bit silly about it. At this point, the author has baked permanent consequences in. No matter what happens, the Rumbling is now a thing, and hundreds of thousands to millions have already been killed. They're not coming back. So there is going to be some major fallout no matter what. If the author plays it fairly straight with the world building until now a few factors point at game theory'ing out a rough outline:
- Titans were going obsolete. From what we see, world was at like WW1 to WW2 era. Which means within a few decades the tech curve would be taking off and there'd be missiles, jets, spy sats, and nukes. And that'd be it, hydrogen bomb Paradis and its walls, good bye threat.
- The rumbling destroys vegetation and animals too. Yeah, Paradis' enemies are wiped out, but so would much of the planetary biosphere. That would likely result in their deaths anyway.
- And you might say, well Eren and everyone else there is a primitive hick, what would he know about this?
- Except that Eren has the whole future memory thing going. So he should be able to figure out both leaving things static and tanking worldwide oxygen are losing moves, even if he doesn't know the exact mechanics of why he has a vision of everyone incinerating/choking.
- Giving his old comrades the freedom that is his raison d'etre is going to appeal to him as well.
- So it's genuinely a decent though coldblooded strategy to enact a for-real worldwide devastation plan, that to the world is obviously going to work, but have initial primary damage be done to a country the world wasn't fond of and had used the titans themselves anyway, and then have Paradis/Eldians themselves stop him and save everyone. The gratitude for that would be combined with the Rumbling being eliminated as a threat, and titans would be slowly neutralized too.
- Presumably queen/kid fit in here somewhere as a head of state to negotiate with/maintain control or something.
Time travel stuff usually stinks so that's a valid criticism anyway. And who knows, maybe he's going to do something like have Ymir be freed and all the titan powers go away or something too. But taking those deus ex machina things as a given, dunno, something along the lines of the above doesn't seem like it'd be too weird.
However it goes it's still been more of an amusing finale then many of these let alone isekai#13901823091283109.