It's dwarves vs dragons in this origin story for Enge's signature character, Morlock Ambrosius
Before history began, the dwarves of Thrymhaiam fought against the dragons as the Longest War raged in the deep roads beneath the Northhold. Now the dragons have returned, allied with the dead kings of Cor and backed by the masked gods of Fate and Chaos.
The dwarves are cut off from the Graith of Guardians in the south. Their defenders are taken prisoner or corrupted by dragonspells. The weight of guarding the Northhold now rests on the crooked shoulders of a traitor's son, Morlock syr Theorn (also called Ambrosius).
But his wounded mind has learned a dark secret in the hidden ways under the mountains. Regin and Fafnir were brothers, and the Longest War can never be over...

The tale of the early days of Morlock Ambrosius--master of all magical makers, wandering swordsman, and son of Merlin--concludes
From beyond the northern edge of the world, the Sunkillers (undying enemies of everything that lives and breathes and is an individual) are reaching into the sky of Laent to drain out its light and warmth. Their hope is to scrape sky, land, and sea clean of mortal life and return to where they once dwelled, before the first rising of the sun. Against them stand only the Graith of Guardians, defenders of the peaceful anarchy of the Wardlands. But the agents of the Sunkillers are abroad even in the Wardlands: plotting, betraying, murdering among the Graith.
Married now for a century, Morlock Ambrosius and Aloe Oaij will take different paths to counter the threat. As Aloe ferrets out the enemy within the Graith, Morlock joins forces with his sister, the formidable Ambrosia Viviana, and crosses the monster-haunted plains of the deep north to confront the Sunkillers in their own realm. Morlock and Aloe think their parting is temporary, but it is final. They may or may not save the world, but they will not save each other, or themselves.

Their conquest was measured not in miles but in degrees of longitude. They smashed the gates of empires, overthrew kingdoms, diverted rivers, and depopulated entire countries. They were the Mongols of Genghis Khan, swift and merciless but also resourceful, bold, and cunning. Their tale has seldom been told in the West, and never by an author with the acumen of Harold Lamb. Ride with young Temujin as he outwits schemers and assassins and rises to conquer Asia as Genghis Khan. Venture to the land beneath the northern lights on a mission of vengeance with Maak the Buriat. Stand with Aruk the gatekeeper and Hugo the Frank as they hold the pass against the Sungar hordes. Lamb's action-packed Mongolian stories, available here in one complete volume, restore the Mongols to their place in history, portraying them not as mindless barbarians but as men of honor and bravery who laid down their lives for their leader and their lands.