Back when the Dinobots first came online, the Autobot mechanic and inventor Wheeljack designed the Dinobots to mimic the Dinosaurs so well.. that he made the mistake of giving them smaller brains. This was a terrible mistake as they all turned on the Autobots and had to be shut down. All seemed hopeless in the fight to stop the new Decepticon Gestalt Devastator, but Wheeljack had an idea and designed larger brains for all 5 Dinobots, allowing them to escape their primal urges occasionally and think for themselves. Once re-activated they became a veritable fighting force against the Decepticons and a definate advantage for the Autobots. Through vorns of trying to fix their internal circuitry from battle, and their original flawed construction, their effectiveness and personalities were hindered. But the Dinobots true potential laid deeper within their core matrix, waiting to be unleashed.
Using the new Predacon technology, Grimlock's spark was transferred into a brand new body. Along with some of his fellow Autobots like Kup, now going by the name of Rattrap. After awakening from his stasis, Grimlock opened his brand new eyes for the very first time. He saw the whole world in a whole different light.. his primal urges were controlled. And he was finally able to talk like any other Cybertronian. All circuitry was brand new, and his thirst for battle was re-kindled. In battle, Grimlock is known to not only destroy his enemies, but annhiliate them with deadly precision. Battle stories from Kup were his favorite pasttime, and Kup would amuse Grimlock as well as all the other Dinobots with them. Kup, now known as Rattrap listens to Grimlock's stories for a change, as they converse of times past and present. Grimlock has an established friendship and an unusual trust with K-9, as Grimlock is the only one who knows who K-9 used to be. As for Grimlock's yearning for leadership, he has felt no urge to try and usurp power from the Maximal elders without his fellow Dinobots. Most of them were considered destroyed by the Swarm.. but Grimlock knows that they are alive and functional. And as soon as he finds them, he will have to question everything he has become, and determine if leadership is what he still wants; And being that he is a Maximal attack specialist with Autobot experience and combat skills, he might just find a way to get it. Peacefully.... or not.