Grima

Grima is the main adversary and final boss of the video game "Fire Emblem Awakening". He is the powerful fell dragon that destroyed Lucina's family in the future.

In the game, Grima time-traveled into the present in order to keep Lucina from preventing the ritual that would already awaken him. It was shown that he formed a secret alliance with Validar. When he first interacted with Chrom and Avatar, his (humanoid) appearance resembled the Avatar's looks. Later on, after Validar's defeat, the fell dragon was awakened and Grima began to stir in chaos. After the final battle, if Chrom delivers the final blow, he would go back to his slumber; but if the Avatar delivers the final blow, both he/she and Grima would die. Either way, he was defeated in the end.