The ex-capital city of the Amestrian city states, Xerxes, was indeed erased from the face of Galbar. However, the old site of Xerxes has been claimed by Farxus to create a city for the undead and forsaken (link
). Although this does not stop you from teaming up with him to create some buildings there.
The rest of the Amestrians don't seem to care much about Xerxes any more. They are out to care for their own cities. There is war and conflict between them and with other tribes. This might still be a good environment for Legio to do things in.
Something which might also be of interest is that the elementals of Galbar are currently waging a civil war, and there is significant collateral damage to mortals. The greatest casualty so far is Dundee, the capital city of the dwarves, which has just been conquered by a bunch of fire/lava elementals.
We have a few sources of appreciable divine essence which might be found as just 'lying around'.
Relics of Perfectus, scattered across the universe by Vowzra, can contain enough divine essence to create a Demigod. This was, in fact, exactly how Lazarus became a demigod. Normally, you wouldn't find more than one Relic per planet, but we can make exceptions to that without any trouble. This is probably the most likely 'divine shard'.
The Winds of Change, which permeate Galbar, are straight up Zephyrion's divine essence. They couple strongly to elementals, which is a favourable property. Urtelem know how to capture the Winds of Change, although they would be adamantly opposed to any plan involving the sacrifice of sentient beings, but others could probably figure it out. The catch is you would need an enormous amount of the Winds to have any chance of producing a divine being.
Arksynth is, in a sense, the flesh of the luck god Vakarlon. Normally, the divine essence associated with Arksynth is far, far too dilute to have any divine effect. However, Vakarlon also favours underdogs, which it sounds like your mortals are. It's a million to one chance, but when you have Vakarlon's favour million to one odds happen nine times out of ten.
Alternative to mortal-driven endeavours, I can think of a couple of other candidate gods who might help possibly, if their players consent.
) is currently in the business of righting divine injustices. Whether creating Legio aligns with that, that might require a bit of readjusting. (Perhaps if, instead of a mass sacrifice, all these people had been slaughtered by some divine cause, then Belru could gather up their souls and put them into a new being. Maybe.)
) is the goddess of Soul Manipulation, which sounds suitable for the task at hand. However, she might not be supportive of a mass sacrifice, although she's so whimsical it's hard to tell.
Vestec the god of Chaos (@Rtron
) is always looking for ways to get more children. Cramming a couple hundred souls into one body and adding a bunch of fire magic sounds like a suitably chaotic thing for him to do. And if these mortals are sufficiently desperate, they could conceivably pray to Vestec, and Vestec has the highest prayer answer rate of any of the pantheon.
We have no shortage of ways to jury-rig together Legio's creation.
(Also, you aren't actually required to start by saying 'wow'. That appears to be some outdated meme from Divinus versions past. But don't let Kho know I told you that.)