The historical record of Djerduth contains little in the way of a lot of direct actions on its part. It is mostly a record of ‘his’ followers and sects.
Information Sources: Mundane Reference | Associated Phenomenology Only | Specific Lore
Djerduth was really only given the label of ‘god’ after its power was focused and corrupted when venerated by the Lich Kings. It was initially thought of more of an great animus source, though it would answer to those seeking to enforce the natural cycle of things. The Lich Lords made it empowered by murder and mass killings of an entire kingdom. It has little material to offer those who would truly further its purpose now – rotting corpses, writhing maggots, the sweet stench of decay; these things are pleasing to it. Much like Mog Creoch. When Djerduth was the death “god”, it personified all aspects of death, with purpose.
Fallen Sacred Spaces: When the Lich Lords took control of the death gods power, they were able to operate through his sacred places. Once this was discovered, they were nearly all burned or razed to the ground. A few powerful old adherents were able to still draw on his power and re-sanctify several places – most hidden – though the caretakers of most of them have long since passed and they are forgotten.
The unreasoning worm Mog Creoch is much easier to trade for power, and the “followers” of it are rarely more than those seeking personal power from a source that generally could care less the type of individual that serves them, as long as the outcome is headless bodies, sundered corpses, and spilled blood. The once unheard of god only maintains his worshipers through this granting of power, but has little then to offer those who would truly further his desires – the feel of rotting corpses, the sound of writhing maggots, the sweet stench of decay; these things are pleasing to the manifested deity. The active process of decay and death nourishes the living and is the order of things so that life may begin again.
In reality, the lich lords of the north stole their power from the god they venerated – a demiurge once part of the natural order, now raised to god-hood and empowered by murder and mass killings, driven insane by the corruption of its nature.
This fact is only known by the druids of the land, and only realized after a long period of thought, study, and melding with the land. Though all work to defeat the evil lords in the north, the druids seek reconciliation – they have no wish to see the spirit loose all its power with the casting down of the winter host. Death run amok, random and without reason would be a nightmare worse than the host itself. Or, death unknown to the living in which the natural cycle is broken in favor of life only.
A Tradition in Hiding: The Narcosa Guild of Salth Marsh – a Necromancer’s brotherhood – still venerates the ancient death god. The animate dead are merely tools to them. They seek knowledge of the body and are decent healers and physics. They carry on some of the rites and rituals and are said to be able to gain Piety from the god, who looks favorably upon their actions. They keep this association as quiet as possible.