A Keychain (キーホルダー Kīhorudā ) is a magical piece of equipment that modifies the appearance and abilities of a Keyblade. In Kingdom Hearts 358/2 Days, the Gear Panel function replaces Keychains, and in Kingdom Hearts Re:coded the Keyblade Chip in the Gear Matrix replaces Keychains. Likewise, the Card system replaces Keychains in Kingdom Hearts Chain of Memories. Cards, however, do not affect appearance, only ability.
Power
The Keychains have the ability to change a Keyblade's stats, grant it special abilities, and give it a new appearance. While most Keyblades have a basic form, like the Kingdom Key, a Keyblade wielder can upgrade and change the form of the Keyblade with a Keychain. In other words, when Sora or another wielder is equipping a "new" Keyblade, he or she is equipping a different Keychain to the Keyblade, changing its form.
Origin
It has not yet been explained exactly what a Keychain is and why it has the power to transform the Keyblade. A wielder usually receives a Keychain after "completing" the events that transpire within a world, but with a few exceptions in which the protagonist is shown being given or finding a token, the Keychain simply appears in their inventory without explanation. These Keychains are often modeled after elements of the world from which they are received in some way.
Exceptions
Sometimes, a Keyblade does not possess a Keychain. For example, the incomplete Keyblade of heart was missing a Keychain, as are the abandoned Keyblades which litter the Keyblade Graveyard.
Tokens
Kingdom Hearts
KH I Ultima Weapon
Kingdom Hearts II
KH II Ultima Weapon
Kingdom Hearts 358/2 Days
Kingdom Hearts Birth by Sleep
KH BBS Ultima Weapon
Void Gear (Vanitas)
Kingdom Hearts Re:coded
KH Re:c Ultima Weapon
Kingdom Hearts 3D: Dream Drop Distance
KH 3D Ultima Weapon
- Flame Liberator Keychain KH3D.png
Kingdom Hearts χ
Kingdom Hearts III
KH III Ultima Weapon
- Way to the Dawn Keychain KHIII.png
- Nightmare's End Reality Shift Keyblade Keychain KHIII.png
- Mirage Split Reality Shift Keyblade Keychain KHIII.png
- Combined Keyblade Keychain KHIII.png
- Destiny's Embrace Keychain KHIII.png
- Kingdom Key D Keychain KHIII.png
- Kingdom Key W Keychain KHIII.png
- Master's Defender Keychain KHIII.png
- Wayward Wind Keychain KHIII.png
- Ends of the Earth Keychain KHIII.png
- Flame Liberator Keychain KHIII.png
- No Name Keychain KHIII.png
- Void Gear (Vanitas) Keychain KHIII.png
- Young Xehanort's Keyblade Keychain KHIII.png
- Χ-blade Keychain KHIII.png