Maleficent's Raven

Diablo is Maleficent's pet raven who originated from the Enchanted Dominion and is a minor antagonist in Kingdom Hearts II, Kingdom Hearts Birth by Sleep, and Kingdom Hearts 3D: Dream Drop Distance. He originated in Disney's .

Kingdom Hearts Birth by Sleep
When Prince Phillip and Aqua are trying to escape the Forbidden Mountain, so they can reach to King Stefan's castle to awake Aurora from the spell, Diablo is the first to notice them escaping and quickly summons the goons to attack them.

Kingdom Hearts II
While Flora, Fauna and Merryweather were giving Sora his new outfit, Diablo is seen watching them from high up above the tower's window, higly remaining unnoticed, and quickly flies off. Sometime later, Diablo, brings Maleficent's empty robe to Yen Sid's tower, and the memories of Flora, Fauna, and Merryweather accidentally bring her back to life. Later on, Pete travels to Hollow Bastion to see if the rumors of Maleficent being killed off was true. Just then, Diablo and the revived Maleficent arrives.

Kingdom Hearts 3D: Dream Drop Distance
When Maleficent abducts Queen Minnie at Disney Castle, she gives Diablo Minnie's crown as well as a letter to be delivered to Mickey to lure him back to the castle

Origin
Diablo first appeared as a minor character in Sleeping Beauty. Throughout the movie, Diablo would do all of Maleficent's dirty work, such as finding Aurora in the forest, or keeping Prince Phillip from escaping the Forbidden Mountain. Diablo would stick to Maleficent's side as a loyal pet whenever he wasn't causing trouble for the heroes, but later met his demise when the three fairies turned him to stone and ultimately, a gargoyle on Maleficent's castle.