Yui's Uxie
Uxie is Yui's fourth Pokemon she caught prior to Full Moon's Full Pokemon Journey. It is also the first Legendary Pokemon she owns as of this point. It made its debut in Be Calm and Snorlax!, where Yui introduced everyone to Uxie. In "What's In a Nickname?", it was officially nicknamed Cici by Yui, and even nicknamed the other Pokemon she has.