Domains: The dead, judgment of souls, the Astral threshold.
Era of ascension: Golden Age of Man (~165,000 years ago). Cohort: dead. Died: God War & Long Winter (~75,000 years ago), when the God War so flooded the Astral threshold with unconsecrated dead that his judicial framework broke under volume — he died of administrative impossibility months before the cold reached his last priests.
Worshipped by: The funerary priesthoods of the Golden Age across cultures — the institutional class that prepared the dead for the verdict, that maintained the rolls of the lately-passed, and that argued the doctrinal cases of difficult deaths in tribunal-shaped sanctuaries built specifically for the work. No living culture maintains his worship. (The worships edge is authored downstream on the worshipper, not here.)
Overview
Morvith owned the crossing; Vraskún owned what waited on the far side of it. The doctrine was deliberately divided: the passage of the dead was one rite, performed by one priesthood, addressed to one daemon; the weighing of the dead was a different rite, performed by a different priesthood, addressed to him. This division was theological. The doctrine held that a soul passed and a soul judged were two distinct conditions, and conflating them was the error of the simpler cults. His priests therefore did not prepare bodies; that was Morvith's province. They received the soul once the passage was complete and conducted the verdict.
The rite was tribunal-shaped. His sanctuaries were laid out like courts: a raised seat for the absent daemon, two facing benches for the doctrinal advocates who argued the soul's case on either side, and a sand-filled basin in the center where the verdict was traced in marks the priests then erased. Some funerary cultures of the Golden Age sent every dead through this procedure; some sent only those whose deaths were doctrinally contested; some sent only the great. His cult had the most priestly hierarchy of any of the dead-gods — a soul-weight required a trained advocate, and an advocate required twenty years' formation.
Fall
The God War overwhelmed the framework by simple volume. The wars produced unconsecrated dead at a rate the tribunals could not approach, much less judge — corpses on battlefields with no priest to perform the passage rite, so the souls arrived at his threshold unprepared, and the advocates' procedure presumed preparation. Within a decade the backlog was visible in the texts as an enumerated and growing number; within two, the priesthood was acknowledging in private that the system had failed; within three, the surviving tribunals had stopped pretending to keep up and had begun simply marking entire battles as collectively-judged, which was not a theology his doctrine had ever permitted.
He died of that contradiction. The texts describe his absence from the rite as preceding the cold by months: the verdict-marks stopped appearing in the sand-basins of the major sanctuaries, then in the minor ones, then in the household tribunals where small private cases had once been heard. The priests held the rites anyway, for a while, in the hope of his return; the cold finished them in their courts. What it did to the unjudged dead is not recorded by his cult, because by then there was no cult to record it.
Morvith's worship limped further into the Winter than his did — the crossing was a simpler office than the verdict, and survived longer in attenuated form. The verdict has had no god since.