This is my first post, so if I got anything wrong, let me know.
I’ve been thinking about Harmony, who may be the most powerful being in the Cosmere, since he is two shards. My main question is: could Harmony combine with the rest of the shards to reform Adonalsium?
Here is my thinking on the topic so far. The first challenge would be reforming the splintered shards—does anyone know if that’s possible?
The second challenge would be getting all the shards into one place at the same time, in their complete forms, and vessel-less. Could one of the current vessels, for example, Sazed, claim the other shards, or would it have to be someone new, flaming all the shards at the same time?
The third challenge, and end of my line of reasoning: In his letter to Hoid, Sazed mentions that “the powers I hold are in such conflict that the most simple of actions can be difficult.” -Third Oathbringer Letter. If Harmony has so much trouble reconciling Ruin and Preservation, would any Adonalsium 2.0 be rendered powerless by all 16 shards residing in it?
One final thought. Was the shattering of Adonalsium a permanent, Cosmere-altering event? Or was it more like Pangea; simply the last of several occasions when all the continents (shards) were one. Now the continents are separate, but in a few million years or so, scientists tell us they’ll collide to form another supercontinent, which in turn will eventually separate again. Maybe Adonalsium is different every time it recombines, as the shards combine in different ways, with different vessels.