The formidable fortress of the Demon King of Incarceration was nestled within the Giant Centipede Mountains, whose twisting peaks resembled the slithering body of a monstrous insect. Moreover, the mountains actually wriggled like living creatures. Like a watchful sentinel, the mountain range served as a natural barrier, guarding the Demon King's stronghold and imprisoning anyone who dared to cross its treacherous terrain. Not only did the high walls that encircled the castle protect the Demon King, but they also ensured that any intruders who braved the mountain's deadly embrace would meet with a swift and merciless death.

As soon as one crossed the immense and dreadful Giant Centipede Mountains, the sky above would appear different, transformed by the overwhelming presence of the Demon King of Incarceration. His formidable power gradually spread through the world around him, painting it in his own colors and announcing his terrifying strength to any who approached.

Beyond the Giant Centipede Mountains, there existed no discernible day or night. The blazing sun could not penetrate the veil of darkness that enveloped the sky above the Demon King of Incarceration, and even the blackest of nights could not rival the oppressive shadows cast by the Demon King's Dark Power.

Neither bright nor dark existed under the gray sky. There was just red earth, the Red Plains, and the only other thing that could be found was a dull black mist.

The Black Fog was a knightly order of demonfolks headed by Gavid Lindman, the Blade of Incarceration and the henchman of the Demon King of Incarceration. In order to reach the castle of the Demon King of Incarceration, one needed to cross the Red Plains, the garrison of the Black Fog.

The might of the Black Fog was unmatched. Its knights numbered three hundred, and they had earned the moniker of the Nightmare of Helmuth. Countless armies and orders that had dared to challenge the castle of the Demon King of Incarceration had met their end at the hands of the fearsome Black Fog, leaving no survivors to tell the tale.

Despite the seemingly endless stream of despairing reports, there were those who refused to give up hope. While some were driven to flee in fear, others remained steadfast, convinced that their sacrifice would inspire others to take up arms and continue the fight — even if it meant they themselves would fall on...