For those who have not completed Xenoblade Chronicles, this page or section may contain spoilers regarding the plot. Discretion is advised.
Mechonis (Japanese: 機神, Kishin, lit. Machine-God; English dub: /mɛˈkɒnᵻs/ or /mᵻˈkɒnᵻs/) is a titan in Xenoblade Chronicles. It is the mechanical counterpart to the Bionis, and home to the Mechon and the Machina. Mechonis is locked in an ancient feud with Bionis.
The general appearance of Mechonis is a towering, mechanical black warrior. It has no "true" face, similar to the Mechon themselves. Instead, it has red eyes arranged in an almost church or fortress-like pattern. Its body is clunky and bulky, unlike Bionis' more sleek and graceful design. The giant sword that Mechonis wields is actually the location of the Battle of Sword Valley.
The Mechonis came into existence at the same instant as the Bionis; the creation of their universe. In the far distant past, Bionis attacked Mechonis with the aim of destroying it. They were locked in a "timeless battle" for aons, which ended in a draw when both titan's souls - the gods Meyneth and Zanza - used up too much energy and were forced to go into rest, awaiting the day that they would fight again. The Mechonis lost an arm, and drove its sword into the Bionis' side. From then the two were still, presumed dead by their inhabitants. These huge bodies now comprise the world of Xenoblade Chronicles. The battle later becomes the "creation of the world" story for the people of Xenoblade Chronicles.
At the time of the game, Mechonis is inactive until Egil reawakens it and controls it himself in an attempt to destroy Bionis. Once awakened, Mechonis' model becomes animated and a loud mechanical groan is constantly heard on the Fallen Arm. However, after being released from Shulk's body, Zanza uses the Monado to destroy Mechonis. Egil is also killed in the process, using his last moments to use Mechonis as a shield, wound Bionis, and help the Junks escape. After Mechonis is destroyed, its lower half is all that remains of the titan, with numerous metal beams jutting out of its lower torso.