That did sound painfully like the Calamity. Replace the ones who had been transported to safety with ones who had not, but instead absorbed the energies of Dalamud and Bahamut and been made something else... Perhaps envision that as the source of the Echo, and imagine it spread through others by that detonation.

"I understand what you're saying, I think."

Quite a lot to think about, but it left one question open. "How did the gods get there to begin with? Were they summoned?"