S01E10 — Character Transformation! Amulet Clover!

Ami wants to decorate a Christmas tree with Amu, so after school, Amu and the Guardians shop for decorations. As the group leaves the store, Yoru steals Su's decoration and Su is separated from the rest of the group. Amu, Ran, and Miki search for Su, but eventually call it a night. Meanwhile, Su befriends a white shaggy puppy who is also lost. The next day, Amu and the Guardians search for Su. Su and the puppy come across an X Egg and the two chase after it. However, Ikuto catches the egg and is about to break before Su prevents him by taking the egg. Utau Hoshina interrupts the confrontation and uses a Character Change to take the egg back from Su. But before Utau can break it, Amu arrives. Amu does a Character Transformation with Su, becoming Amulet Clover and purifies the egg.