MSQ
From what we heard through the MSQ, we know that Living Memory is actually the 9th Reflection. Something is actually quite disturbing because I though that only Asciens were aware of the Reflection's existance, therefore, they must have some kind of link to them. Of course, the "Key" is able to connect two world, but Ascien weren't aware of that, otherwise the first arc with the Ascien would have been a lot different and the key in their possession since the start. Since only Emet-Selch has the ability to travel through Reflection, desperately trying to find a solution to unify the world and even causing calamity on his path. Emet Selch could have started all this, then the people of that world would have survived with only their city without him knowing what they managed to do thanks to the Lalafell of Aloalo and the Key that allow for dimensionnal travel arriving at that moment saving the day with their knowledge. So maybe thanks to that, many people become aware of the existance of Reflection and Primitive world and started to search for a solution to save their world.
On an other point now. In the first lvl 100 dungeon, we know that Sphene is supposed to die. So we have multiple possibility here. Either she was in fact severely injured, healed but kept in a coma state and the story we know is true, OR, the story didn't go that away at all and Sphene was never injured but instead "used" to make all this.
Also, considering that the "Fear of Death" is getting more and more on the front of the scene, I start to really think that we have to face Necrom at some point, which is an entity generated by the Fear of Death in FFIX. The goal of Calyx seems to go that way, by offering a limited amount of Black Regulator, he probably want them to feel that fear even more. We know that fear can cause horrible thing if the Dynamis is fucked up like how Meteion created the Apocalypse, and I think that Calyx maybe trying to create that for some reason, maybe to summon Necrom that way, something like a Super Apocalypse entity able to influence the Flow of Death. Calyx seems to search something about "Evolution of Mankind" and Necrom could be the answer to that. By generating the Fear of Death to a certain extent, Necrom can be summon and Calyx maybe trying to take control of him to fulfill his goal.
Raid tier :
I don't know exactly where all of this is going. We manage to vanquish Brute Bomber a second time and conquer the Cruiserweight category. The owner seems to be a complete mad man and I expect him to betray what he said about giving up the souls and the medecine for the disease. He has no reason to not give the medecine to the fighters, or maybe he has some utility for this disease that allow him to do something with it ? I don't know, not enough elements so far to know what's going inside his head.