The Ymir Clan that lived in the Extreme North, also known as the Frost Giants, had the responsibility of guarding the Calamity of Extreme Cold, maintaining, repairing, and passing down seals that might become damaged.
The Dwarves who lived even farther away undertook logistical work... they needed to constantly train and make their race stronger so that one day they could, together with the Frost Giants, completely eliminate the Calamity.
However, after the Divine Era, intense conflicts broke out between the Dwarves and the Frost Giants... back then, the Dwarf King and the Frost Giant King engaged in a physical war that lasted for ten days and nights.
That was the "King Battle," and after the Dwarf King's victory declared the end of the battle, the Ymir gradually went extinct... as did the knowledge of the seals, which gradually faded with time.
