Illgarm is an Ice Demon, responsible for much chaos in the land of Niflheim.
When Illgarm came to Niflheim, he immediately ordered that an ice citadel be built and, while its spires were still rising, he began creating an army out of the tribes of monsters that roam the inland portions of the area. Those who would not join he slaughtered with great efficiency, feeding their remains to his growing army.