The Last Sacrament is a dark and haunting tale set in the universe of Reonon, where war is waged by towering Mech-Knights, living machines fused with divine and dark energy. It follows two brothers, Seihtaal'ek Thraun and Aseir'ithan Thrakuun, both piloting Ælythirra—sentient Mech-Knights bound to their pilots' minds and souls. The story unfolds in the stormy atmosphere of the gas giant Kaeth'Ahn, beneath the looming Cathedral of Silent Voices, a holy structure that houses the ancient faith which binds their war-torn universe. The brothers stand on opposite sides of a cosmic conflict, divided not by hatred but by belief. Seihtaal, disillusioned with the cathedral's manipulation of their faith, seeks to destroy it and end the cycle of endless war and death. Aseir'ithan, however, remains loyal to the cathedral, believing it to be the last thread holding their fractured universe together. As their Mech-Knights—Vokhaal-Inir and Vaeleth-Shuun—clash in an epic battle, the narrative explores themes of faith, brotherhood, and the destructive power of belief. The battle between them is not just physical, but ideological, with each brother trying to convince the other of their righteousness. The fight reaches a devastating climax when both mortally wound each other, their Ælythirra locked in a fatal embrace. As they fall, they realize that neither will survive the battle, but their sacrifice will change the fate of their universe. The Last Sacrament is a tragic, introspective story that delves into the conflicts of faith, power, and the bonds of family, all set against the backdrop of a universe where war is both divine and destructive.