Keychain

The keychains that are attatched to a keyblade are their for few possible reasons. As of one they carry the consciousness or semi conscioussness and will the keyblade itself holds. two the keychains can act as talismans, they 'funnel' or release magic through the keyblade. Each keychain resonates its own type of energy or frequency allowing the keyblade depending on the power and frequency of its carrier/ bearer to have a unique appearance and ability.