This is Micaiah, Leader of the Dawn Brigade, monikered the 'Maiden of Dawn', rallied the people of Daein to liberate themselves from Begnion rule after the Mad King's War and the vessel of Yune, the Goddess of Chaos (Who's also her pet bird!)
Game History:
Micaiah appeared in Fire Emblem: Radiant Dawn. She starts off as a Light Mage. By the end of Part 1 she becomes a Light Sage, and before entering the Tower of Guidance Yune turns her into a Light Priestess.
Specialties:
Micaiah can use light magic, but she is the only person capable of using the light magic Thani. Changing classes into a Light Sage allows her to use staves. She is the only character capable of using Sacrifice, an ability that cuts her HP to heal an adjacent ally with an equal amount.
Moves:
Special: Light
A burst of light hits any opponent directly in her front. This move has minimal chances of stunning the opponent.
Special Sideways: Thani
This chargeable move hits the opponent with a vertical beam of light.
Special Upper: Rewarp Staff
This recovery move warps Micaiah upward.
Special Lower: Sleep Staff
This move can put an opponent to sleep.
Final Smash: Rexaura
A powerful blast of light damages and knocks back anyone within a considerable distance in Micaiah's front. Foes that do not get hit/survive the blow, get stunned no matter where they are on the stage.