Tutelary deity of the sacred crystals fashioned by the gods at the time of the Great Making. Created in opposition to Mitron the Chastiser, scion of light. Upon entereing the world of Man, he was enveloped in the turmoil rampant there. Lost, he died and was reborn countless times, a walker of life's wheel, eventually to rage against the gods that had so fated him. By sitting in meditation upon the Uneh Pedestal does he clear heart and mind until all that has order and reason and thought is made as nothing.

Chaos is located deep within the Necrohol of Nabudis. To reach him, the party must complete the "Waterway Haunting" and "Lost in the Pudding" hunts. After doing so, you must complete the "Nabreus's Medal" sidequest that eventually leads into the Necrohol of Nabudis. Defeat the optional bosses, Fury and Humbaba Mistant, to unlock the path to Chaos.

This Esper adjusts well to any situation. It bases its attacks on the enemy's weakness, so it always hits the opponent hard where it hurts the most. Chaos enters battle with Reflect on, which makes it difficult to heal him when the need arises. Equip and Opal Ring before summoning him to prevent this from being an issue.