Ruins of the Old Empire
When the Curse on the World was unleashed, the most obvious effect was the Tomb Horde. Undead began appearing in great numbers, and while they were not particularly intent on assaulting the Ilmand Empire, they were so numerous that civilization began to crumble.
The Empire was at its peak when the Horde arrived, and did not go down without a fight. It was twenty-two years before the last Emperor died (and another lifetime before the last successor kingdoms finally disappeared), and in that time much was learned.
As with the Curse as a whole, the Horde is animated by the malice of the Triune Evil, the three most powerful of the evil gods slighted by the Empire’s turn toward Amaunator and Pelor. All of the world’s dead, except those cremated and consigned to the gods of light, were returning. They did not do so all at once, but this just had the effect of forever reinforcing the multitude of evil no matter how many times it was blunted. A thousand-year old barrow king or a farmer who’d died the day before could return as a wight or skeleton, while even those who had completely crumbled in their graves would reveal themselves as ghosts and worse.
The Horde was fought in any number of ways, from the development of powerful magical weapons (their secrets now lost, or impossible to reproduce without the resources of an empire), to painstaking attempts to consecrate and burn everyone who died after the Curse came.
In the centuries since the Empire fell, the Horde has slowly subsided. The bodied dead are subject to the forces that affect everything over enough time, and many have crumbled into dust, or been buried by fallen buildings, or swept into the sea. The spectral dead are more problematic, but are thankfully more rare, and are subject to complete dispersal by assiduous priests. Much of Usteidunn remains too dangerous for settlement even down to this day, but there is room for hope that one day the Tomb Horde will be defeated.