A view of CC...

[AuraTwilight]

My theory is that Schala simply undid the events that caused the timelines to split in the first place.

[Zaperking]

The remerger would have to go in a loop, personally speaking.

For instance, if the merger is done from 1010AD, then that's going back in time to unify it. At that point. The Dragon God, FATE, Lucca are alive. So hence, they will all exist now. The Dragon God may be unleashed since FATE would have no more flame, and in turn, FATE would lose power unless it has a backup system, and it only wanted the flame to create it's own spieces.

Maybe if it happens in 1010AD, the timeline progresses to 2400AD where there is no time crash, so then the past changes and there is no Dinopolis/ no FATE... But then there is no El Nido...

So yeah, it's kind of hard how you want to decide. It might be probable that Another World and Home World remerged from the past, but to the people of 1020AD, they'd just realise that certain things are missing, like FATE, The Dragon God, and Lucca would be back.

[Chrono'99]

For instance, if the merger is done from 1010AD, then that's going back in time to unify it. At that point. The Dragon God, FATE, Lucca are alive. So hence, they will all exist now. The Dragon God may be unleashed since FATE would have no more flame, and in turn, FATE would lose power unless it has a backup system, and it only wanted the flame to create it's own spieces.

Whether the merger is in 1,010AD or 1,020AD, the Dragon God wouldn't be alive in the merged dimension, because he ceased to be part of any normal dimension a hell of a long time before both dates (he was absorbed by the Devourer of Time during or some time after the Polis War). The Dragon God and the Devourer of Time no longer exist after the game events.

Why would everything before 1010AD be the same as Another World and shitty?
It probably wouldnt. After all, as you said, its the WHOLE timeline, and all space merging, not just a chunk (Half of teh timeline) from Another World being dominant, and the rest being ideal. In order for it to be ideal, the timeline would have had to lead up to that beautiful time of posperousness and plenty.

In case you forgot, Another World is the "normal" dimension, i.e. the one that exist(ed) before the split (everything before 1010AD is part of Another World).

[Zaperking]

Hmm.

1) Another world is not the original dimension. Another and Home world are pieces to one puzzle. If they're not combined, neither is the original one. Another World simply was not effected by anything drastic like the Dead Sea, and is original since Serge died in it. That's what makes it the so called "original" even though the split should have caused both to stem off from the one like:

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Unless Home World drastically affects Another World, then there is no point to remerge the dimensions... All you're doing is making one set of people more dominant, and destroying the others memories. The reason that the unification is needed is since neither dimension is complete without the other half. So basically, one dimension can be more ideal, but shouldn't be the original.

As for the Dragon God, if time was rewritten in 1010AD, the Dragon God would not have been killed yet, since it only dies in 1020AD. The TD only consumed their body and used that power, but it's still a transdimensional entity so it shouldn't die just because he dies. But even so, if they do die, Harle doesn't since she was produced with the last of their power, and should be physical since she was never devoured.
Theres a whole set of complications if time is rewritten from 1010AD. Time may have changed so much that FATE has been dead for the last 7000 years since FATE is thought to be in the actual future. It's mind racking >.<

[Sentenal]

Home World was said serveral times to be the "false" world, or whatever word they used at the end of CC.  Home World=fake, not original.  By process of elimination, Another World=real, original.