Dreadhearts

Vast, semi-mythical Void-beings, Dreadhearts are the greatest physical threat the progeny of the Thirteenth can offer.

Suneater
Suneater is a vast flying creature, miles long, covered in swarms of flying Void-beast parasites. Suneater's mile wingspan can very easily block out the sun where it flies, and while it hovers calmly above cities, circling lazily, it drops huge bombs of corrupting pus and summons massive storms of tainting gas. Its army of flying and skin-bound parasites are adapted to defend it against any assault.

Of course, this would all be true if Suneater wasn't trapped under Mt. Mara in the Kull Mountains near Mezigo. He was trapped there in the past by the combined efforts of the First Sorcerers and the Mine-Kings of Great Kazzan Minar. His wings are weak, and his parasites are dead, but Suneater lies waiting.

The Winterking
The Winterking is a gigantic, aquatic abomination. His maw alone could swallow a whole armada, then spit it back out, tainted with void. His reaching tendrils, thick as a galleon, can crawl a mile inland and shower poison and sea-beasts on the poor land-bound fools. The sheer wake of his bulk can sink an entire fleet of ships. But the true terror is the coursing icy void running over his skin, freezing everything in his wake and plunging the continent into winter,

Of course, this would be the case if he wasn't pinned under the entire weight of Riole, the Holy Island. Sealed there by the first Kings of Valhallen and Rainemar, with the aid of the Gods, his icy powers are halted, and he himself sleeps, slowly stirring in his underground prison.

The Beast
The Beast, physically smallest of the Dreadhearts, but no less terrifying. In his wake, animals are corrupted - their blood and saliva drip and hiss with the taint of Anti-life. Monstrous pets and disloyal steeds bite their owners, the corruption making its way from the smallest tick up to the greatest king. The Beast itself never tires, never sleeps.

Of course, this would be true, if the Scourge of the Land was not buried a mile deep into the earth in the very northeast of the Great Plains, pinned down by the weight of the Three Pillars, gigantic iron spikes created by Zetron and Zagan to pin the monster down. He lies, bleeding, but healing, biding his time.