Scowl

Scowl is a Decepticon/Dinobot who worked with Thunderhoof in Transformers: Robots in Disguise.

History
He was the wrecker, who destroy their bots' homes who stayed the Thunderhoof's theft of lands. Grimlock befriended with him, but when he and his team come to look for him, he attacked their attack. Grimlock wanted to help him, but he realized that apparently can not help a bot who does not want help. He wanted smash what he want and when he want. But at last Grimlock won him, and then he was taken to stasis pod.

Trivia

 * In addition to the Scowl, another Decepticon named Silverhound worked with Thunderhoof too.