The Iophanite
A messenger of the Martyr, in yellow-white flame over Vëné's grave
An angel: one of the messengers the gods send, and by one account the sort commonly used on battlefields, where a message has to arrive and cannot wait for a rider. It shows as a disc turning in yellow and white flame.
It came to Koa at the obelisk over Vëné’s grave in Vigil. He had gone there alone at night, worn down by what he was carrying and offering himself up for it, and it answered what he put to it. What it gave him is the reason the party believe the thing under Haudh-Gwenn can be undone at all: the souls in that ooze were joined by alchemy, and what alchemy joined, alchemy can part.
Both things it told him held. Mikhail and Professor Ashanti al-Hassan burned the ooze at dawn after three seasons of work on it, and it came apart along exactly the seam the angel had named: the souls of the people melted into it went out of the world one way and the bound water-elemental matter went the other, disjoined for the first time in hundreds of years. And its word that Vëné would come back when the curse broke was good, if modest. She came back and did not leave.
Whether the Iophanite is a single being or one of a kind is a question the party have asked and not settled. The same messenger is thought to have spoken to the Elder after Vëné fell, but the strongest word anyone has put on that is likely. Mikhail went looking for scholarship on them afterwards and came back with nothing. Erôth does not appear to have written any down.
It has appeared once.