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The One-Winged Angel resembles Sephiroth's Masamune sword, although its handle and blade differ in keeping with the design of a Keyblade. The Keychain's token is one of Sephiroth's wings, hence the name, and the teeth of the blade resemble the spell Meteor. The Keychain token is tied to the hilt with a red cord.
In battle, the Keyblade becomes completely engulfed in flames when it is swung. This may be a reference to the Nibelheim Incident seen in the Compilation of Final Fantasy VII, in which Sephiroth razed a village to the ground.
One-Winged Angel is named after the famous battle music played when fighting Sephiroth in the Kingdom Hearts series and the Compilation of Final Fantasy VII. The name "One-Winged Angel" refers to his Safer form from Final Fantasy VII. Despite resembling a Seraph, a six-winged angel, the title refers to the multi-colored wing that replaces his entire right arm. Since then, in almost all of Sephiroth's appearances he has been seen with one large black wing on his right side.
While its stats are low for a Keychain awarded for beating Sephiroth, its powerful critical hits allow it to rival the Ultima Weapon in power.
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