Key, Lock, He and I! / Character Transformation! Platinum Royale!.Key, Lock, He and I!: Yukari tells Kairi to obtain the Humpty Lock from Amu. During a meeting, Kairi stares at Amu and the other Guardians believe he is in love with her. The next day, the Guardian Characters hold a secret meeting and El brings the lock with her. When Il and Yoru show up, a fight erupts. Amu and Kairi find the Guardian Characters and Kairi obtains the lock. Tsukumo, who works under Yukari, steals the lock from Kairi and runs off. Ikuto appears, praises Kairi for his "good job", and goes after Tsukumo. Amu attempts to Character Transform, but cannot without the lock. Ikuto, as Black Lynx, catches up with Tsukumo and stops him. When Amu catches up, the Humpty Lock and the Dumpty Key react. Ikuto tries to open the lock with the key, but Amu becomes scared and the lock rejects the key. Ikuto returns the lock to Amu and leaves.
Character Transformation! Platinum Royale!: Easter is implementing its new project, the Black Diamond CD. It is rumored that a person will have their wish granted if they listen to it. Kairi slips one of the CDs into Tadase's bag. Tadase and Kiseki get into an argument and Kiseki runs off. At home, Tadase finds the CD in his bag. When Kiseki returns, he finds Tadase listening blankly to the CD and Kiseki becomes an egg. Kiseki goes to Amu for help and they find Tadase with a group of other children around a van playing the song from the Black Diamond CD. The music extracts X Eggs from everyone and an X appears on Kiseki's egg. Amu snaps Tadase out of his depression, and Tadase and Kiseki Character Transform into Platinum Royale. Together, they round up the X Eggs and purify them. Among the eggs, one sparkles more brightly then the others and disappears.