Huh, Prow, I thought the point of the Dragon Break was that they wanted to make Akatosh the only "real" one, because Akatosh was the pro-human mix up of Alduin/Auri-El's traits with some of Shezzar's human-friendly things, minus all the bloodshed and elf-killing but he was still made up later, by a human, and based on the original Time-As-Destroyer aspect, and then having Akatosh and Auri-El being a little too distinct for a while.
Aside from the Maruhkati Dragon Break there three other events in which time breaks down. The Warp and the West, the Apotheosis of the Tribunal and Dawn Era. These three have in common that there are always were several gods about.
Do not ask us where we were when the Dragon Broke, for, of all the world, only we truly know, and we might just show you how to break it again.”- WWYWTDB, Mehra Nabisi, Dunmer, Triune Mistress of the New Temple
Originally you could derive it from this. The Tribunal knew how to break the dragon.
How do you think I learned my mystery? The Maruhkati Selectives showed us all the glories of the Dawn so that we might learn, simply: as above, so below.”- WWYWTDB, Manimacro
This also helps. The Dragon broke is equated tot he dawn era.
The Jills did not have their full powers; rather, I should say, all the mundex spirits had every power at every time amendment at every ordering, which is to say none of them could ever fully express; our world was young and so were its architect gods. - Intercept
Later on from this. It simply says gods have control over time. Which both the previous bits are hinting at.
So this suggests that during the Maruhkati break there were also gods around*. But which gods could there be? Since the Aedra are all dead and gone it won't be them. The only candidates left are the Selectives. Their motive was to remove elven aspects from Akatosh, but if this proves impossible, then the only thing to do is to remove the Nine and replace them. Cyrodiil could have ended up like Morrowind with Nine God Kings instead of three.
I don't know why it ended but I suspect the situation had become such that they could no longer go on. Perhaps they got caught up in mirror wars.
*Not the strongest form of reasoning but you'd expect some consistency in your story telling.
edit:
Actually the spore dream suggest that an attempt to play the remainder of it was made and resulted in the activation
adachimelic holding-tendrils, which sounds like spokes to me. From Vehks teachings we know that these come loose when there are gods about so this may have happened during the MDB. This means that the whole lot evaporated.
I suppose adaptation may be as good a word as a remake, if we're using fiction words. A sort of updated re-release made to be more appealing to the current audience. Still, though, Akatosh and Alessia were not the main thing holding the dividing lines up. If Uriel and his sons had been assassinated six years before Morrowind instead of six years after, then the Gates would have opened as soon as the Heart was released, at least that's what I've always thought.
No indeed. The Empire has been often without an heir.