Gamekeeper

Deep beneath in the caverns of Aquatron lurks the Gamekeeper. A gigantic, cybernetically-augmented crustacean, this monstrosity considers itself to be the most successful creation of Inquirata. The Gamekeeper tends to the many creatures who see use in Quintesson show trials, including the Piranacons and the Eelcons, but if those victims escape their appointed punishments, then the Gamekeeper must take more direct action- and few survive its final judgment.

Transformers: Retribution
When the Quintessons first arrived on Aquatron, the Gamekeeper ate several Sharkticon rebels. According to it, "they tasted sweet".

Much later, Optimus Prime and Megatron found their way into the caves after they were disposed of by the Quintessons. They stumbled across the Gamekeeper, who taunted the two Transformers about the impending Quintesson invasion of Cybertron. The Gamekeeper's mockery enraged Megatron, who immediately tried to kill the monster. Optimus managed to restrain it long enough for Megatron to rip out its eyestalks and stab it with a nearby stalactite. The Gamekeeper died soon after, but not before telling the two leaders about the original Sharkticon rebellion.