Monument Stronghold (碑堅陣 Hikenjin ) was the powerful defensive formation used by the Crimson Lord "Barrier of Burning Dust" Sokar, one of the Nine Eternal Divine Scales and Töten Glocke's Front Line Army General. It takes the form of large stone trees which cover the surrounding area, forming a black forest.
Sokar could freely move the trees and individual branches of trees in the forest, and aside from supporting his army or allies, he could freely transform trees into giant hands or spikes and directly attack enemies who were inside the forest or above it. He could also advance the black forest itself to engulf and destroy enemy armies.
Sokar's body was hidden within the forest and was the core of the Unrestricted Spell. He was able to grasp what was happening inside the forest and control it without having to move, so it was difficult for him to be found. Sokar's fellow Front Line Army General Ullikummi had called him "crafty, sly and detestable", and this statement may also fit for Monument Stronghold.
Monument Stronghold was a powerful Unrestricted Spell in halting a large number of enemies such as an army, and thus it was used as an unbreakable barrier to protect Asiz. Its power along with Sokar's excellence in battles meant that it had been undefeated until the Great War of the Middle Ages.
Due to the Flame Haze "Archer of Aurora" Karl Berwald's reckless commanding, charges, and isolating himself for a one-on-one fight, Sokar let his guard down. Misreading Karl's power, Sokar revealed his real body and directly attacked him. Due to this, Sokar was destroyed by the power of Karl's Divine Vessel Zorya and Gripen's Howl and Draken's Roar.