The Gazing Eye

Master Xehanort's Keyblade (マスター・ゼアノートのキーブレード) is the Keyblade used by Master Xehanort and his more youthful incarnation "Terra-Xehanort" in Kingdom Hearts Birth by Sleep.

Although Master Xehanort does not often draw his Keyblade, whenever he does fight he wields his Keyblade in this form, even after becoming Terra-Xehanort. Xehanort often uses this Keyblade to channel his own dark magic, but the Keyblade itself also possesses the ability to lock and unlock hearts. Master Xehanort once used this ability to extract the dark half of Ventus's heart from his body, creating Vanitas, and then again during the final battle at the Keyblade Graveyard, in order to extract his own heart and allow him to take over Terra's body and become Terra-Xehanort. However, during his battle with Aqua, Terra's heart is able to take over long enough to use the Keyblade to seal away his memories, which also causes him to lose the power to wield a Keyblade. After this, Master Xehanort's Keyblade vanishes.

Design
Master Xehanort's Keyblade has a spiky, black guard resembling demonic wings, a horned, demonic head just above the handle, two barbed shafts, and teeth resembling a battle axe split into three almost claw-like protrusions. It resembles the Oblivion Keyblade to a degree, but with two shafts and a different head. It also contains two demonic, blue eyes; one above the handle and the other one on the head, similar to that of the Soul Eater, Way to the Dawn, and Void Gear. Its shaft and head are adorned with several twisting, silver patterns. Master Xehanort is capable of converting his Keyblade into an orb of dark energy, which is shot into the sky to summon Kingdom Hearts. His Keyblade possesses a Keychain, which has a black charm with another demonic blue eye upon it.