Drago's Bewilderbeast

This foul, sad, wrethched dragon was presumably captured and enslaved by Drago Bludvist and his forces at some point in the past (possibly by mobilizing by a mass of men and modern weapons), and might have been tortured as well. Now, he is nothing more than a weapon, a tool, and a slave to the villain.

Characteristics
Comparison to the other one, this individual is dark and looks very menacing, tyrannical and violent. Additionally, he seems restless and being always enraged. It is not sure if this dragon's true nature is evil, and is possible that he originally had a normal, peaceful character. Understandably, his behaviors are unfriendly and destructive and doesn't care about damaging the mad person's forces.

Trivia

 * It is unclear whether this Bewilderbeast can be classified as a tamed dragon because he was enslaved by humans likely against his will.
 * Drago seems succeeded to enslave this Bewilderbeast quite effectively, as the beast doesn't look mind of letting the man on the dragon's head.