Defeated by Manus and the Abyss, Artorias sacrificed his great shield to protect his loyal companion, a young Sif, from the myriad Humanity Sprites that littered the deepest reaches of Oolacile. With his left arm shattered following his confrontation with Manus, he had no use for the shield and chose to wield his greatsword in his one good hand. With time, Artorias became fully-corrupted by the Abyss (though, in hunting the corrupted denizens of Oolacile, it is clear he didn't wholly forget his mission). At some point after this, an unknown hero (The Chosen Undead) travelled back to the past and, in the process of relieving Oolacile of its corruption and rescuing Dusk, finally bested Artorias.