The High King's Tomb. Book Three

With the ghostly help of the First Rider, Karigan G'ladheon had transported the corrupt spirit of Mornhavon the Black into the future, buying valuable time for her king and country. But how far in the future is Mornhavon now? A hundred years? Ten years? Only one year? There's no way to tell. So though the immediate threat has passed, Mornhavon's shadow still lies heavily on the land, and on their minds ...
although there are threats closer to home as well. The D'Yer Wall, protecting Sacoridia from the dark, corrupted Blackveil forest, remains breached despite Karigan and her fellow Riders best efforts. They've scoured the land searching for lost documents and magical clues to help mend the breach, fend off any incursions from Blackveil Forest and, more pressingly, protect them from Mornhavon's return.
Nor is the breach in the wall the only danger. Mornhavon may have gone, but the descendants of his people remain and they're ready to claim the land that their forefathers failed to conquer. These vengeful enemies, hidden within the peaceful borders of Sacoridia, have spent generations honing their dark magic ready to strike - and ensuring that their blow, when it comes, will be one that Karigan and the Sacordians have no defence against ...