Drogoth
From Tolkien Gateway
Drogoth the Dragon Lord is a non-canonical character in EA's The Battle for Middle-earth II and The rise of the Witch-king. He is a playable character for the Goblin faction.
Drogoth is said to be the lord of all dragons after the death of Smaug. He can only be attacked by archers and catapults. Drogoth has a variety of powers, and is considered by many to be one of the most powerful characters in the game.