Who are the shadowy forces behind the endless tide of frozen invaders from the Nocthian Caldera? Why do they hate the dragonborn of The Remnant Dynasty so much?

Originating deep in Midnight Peak, the dead volcano at the heart of the Nocthian Caldera, a swarm of creatures large and small arise every winter to assail the only pass into the Dynasty. It was 90 years ago when they swept out of the dark, bringing winter in the heart of Midsummer, leaving the land snow-covered and icy behind them. The first wave was rime wraiths, elemental creatures from the Plane of Ice. Each wave sapped the heat from the ground and the defenders of the Old Dynasty alike. Following behind them were frost worms--wingless, belly-crawling monstrosities that breathed shards of ice and whose trails froze the ground down to the bedrock--and frost giants, 25' tall, blue-skinned, rune-adorned merciless warriors who swept the dragonborn before them. Broken, the survivors of this assault retreated down the Last Resort Pass, a 70-mile stretch of mountains once carved by a mighty river, now frozen solid at the source. They managed to turn the tide at great cost at the head of the pass, and the two have fought over those first few miles ever since.

Leadership

The ultimate driving force behind the Hungering Frost resides in the demi-plane of Ice. The Titan Isskap, who fled there at the Breaking and gave herself to elemental Ice in exchange for retaining a large part of her original power. She is driven by a desire to see her children, currently preserved in ice against the degeneration inevitable to all titan-kin after the First Wish, restored to life and ascended to godhood. The sacrifices necessary to preserve them and herself have left them tainted by the Abyss; she needs a focus of runic power to banish the taint and catapult them to ascension. Until that day, she maintains effectual control over the demi-plane and its inhabitants, although she constantly must fend off rebellion and undermining by her vassals. Her ability to act directly on the mortal plane is limited--if she pushes too hard, she'll incur the wrath of the 3rd Celestial Legion contingent stationed in the Plane of Water.

The day-to-day command of the forces of the Frost resides with Xol'cerd, an adult white dragon. As a wyrmling, her brother was killed by adventurers in the days leading up to the Cataclysm. As they were dragonborn, she has vowed to destroy all dragonborn in retaliation. She hoards any and all magic items she can.

The leader of the barbegazi forces is <NAME1>. While he fears Xol'cerd enough to stay in the alliance, he is desperately looking for a way to end the war that has killed generations of his people.

The leader of the giant-kin is <NAME2>, a troll-blooded Everlasting One. After the defeat at the Pass 5 years ago, he has withdrawn much of his forces to the north to prosecute a war against Hammerhead. A few remain with Xol'cerd, mainly ice trolls and ogres.

Forces

The forces of the Hungering Frost are of several kinds: the goblinoids, the giant-kin, and the beasts.

The bulk of the forces are ice goblins, called barbegazi. Larger and more solid than regular goblins, these goblins have traded much of the racial memory and ability to create hobgoblins for individual prowess and hardiness. Commanded by <NAME1>, they ride wargs and partner with winter wolves. They also build the siege equipment used against the Wall and form most of the raiding parties into Dynastic territory.

The giant-kin have migrated via portal from Oelfra. Born to fight, the frost giants are few in number but individually powerful. Along with them are several hill giants, stone giants, and many ogres and trolls. Mostly mercenary, they are commanded by <NAME2>, but have largely retreated to the north to fight the dwarves of Hammerhead for their own reasons.

The beasts, spearheaded by the ice wurms, are under the direct command of Xol'cerd.

The Runic Lexicon

The object of this war is the Runic Lexicon. A rune-carved gem about the size of a fist, it holds immense power over the elements and reality itself. Carved in the First Days, it lies mostly inactive until someone with the knowledge and power to wield it takes possession. Currently housed at the tip of the royal scepter of the Remnant Dynasty, it has granted the rulers a tiny fraction of its power. Crucially, they do not know what it is and no records still exist. But Isskap knows. She will do anything she can to acquire it.