Transformers: Timelines
In a story from the Transformers Collectors Club for 2013, several Autobots land on Shattered Glass prehistoric Earth. In order to survive the Energon radiation, Prowl combines Pretender and Headmaster technology in order to create animal-based alternate modes for himself, Ironhide, Silverbolt, Grimlock, and Ultra Magnus, making them into a team similar to the Maximals of Beast Wars.
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