In the past, when the frost and snow fell and the moon disappeared from the sky, the Frostmoon Demon Beast Thysdyr would awaken from his sleep and cause destruction everywhere. At the time, the people had no way to stop him, so they could only flee. They would wait for Thysdyr to leave, then return to rebuild their homes. The villagers lived through this nightmare year after year, until one year at this time, a strangely-dressed traveler came to visit even though he knew the terrible beast would attack.
That night, as Thysdyr's angry roar drew nearer and nearer, the traveler sat in the empty city, quietly waiting...
The next day, the villagers returned to find their village untouched. Surprised, they asked the traveler what had happened. It turns out that Thysdyr was afraid of rune-catalyzed flame. This exciting news spread quickly to all the nearby villages. After that, every time the Frostmoon Beast awoke, he could only continue to hide in the darkness.
Many years have passed, and Thysdyr hasn't been seen for a long time. But every year when the snowy season arrives, people build a giant pyre and dance around it, throwing in rune catalysts. They celebrate day and night, and call the celebration the Festival of Fire.