Originally Posted by
mightyg
Yeah Hydaelyn's blessing of light clearly shields the player character from being tempered. This was made clear by the first encounter with Ifrit. I would assume Diabolos and Siren are also primals, at least in a sense. I think they implied that Diabolos was summoned by the people of Amdapor and was the partial cause for their demise. He says something along the lines of being weak from his long slumber. It seems like Primals are capable of manifesting themselves albeit slowly. Siren seems to feed off the charmed sailors as well.