Chaos Castle, a battlefield forged by Lugard, the God of the Heaven World, and Secrarium, the God of the Underworld, serves as an arena to maintain the balance between good and evil. Over time, participants began favoring Lugard, tipping the scales. To restore equilibrium, Secrarium proposed that all combatants wear the Armor of Guardsman during battles, a suggestion Lugard accepted. Today, Chaos Castle stands as the ultimate proving ground, where players face off against each other and underworld warriors, vying for prestige and prizes without fear of death penalties.