Riku finally managed to break off a crystal, looking it over before pocketing it.

The teen shrugged at the questions, but still kept his smirk. "When you change the keychain, the Keyblade changes. It draws power from the keychain." He held up Way to the Dawn's keychain as much as a gesture as an example. "If an object resonates with the wielder and the Keyblade, if it's attached the Keyblade'll change shape."