Blaster and Goldbug could not endure Grimlock's leadership any more, and set out on their own, only to have Grimlock mark them as traitors.

Realizing that Grimlock had become trapped in a " chrysalis " stage, Prime's Powermaster partner, Hi-Q, tapped into and accelerated the process, completing Grimlock's evolution into a more powerful " Actionmaster " – but the enhanced power came with a price: Grimlock was now no longer able to transform into dinosaur mode.

Enraged, Grimlock refused to take orders from Optimus Prime any more, and led the Dinobots away from the Ark.

By the Earth year 2005, it seemed apparent that Grimlock had undergone some degree of a personality change, becoming more childish and petulant, rather than brutish and stubborn.

Transformers were no longer as simple as they were in his day-surrounded by Pretenders, Headmasters, Micromasters, Powermasters and more, Prowl and his fellow old-schoolers longed for the old days, and when Grimlock suggested the creation of a proactive Earth-based Autobot force, they were quick to volunteer to join, that they might recapture some of their glory days in a simpler conflict than what the larger war had become.

In order to protect themselves against Energon surges, the Dynobots required alternate modes covered by a layer of synthetic flesh ; Grimlock refused to transform into Ice Age mammals and made the decision to go with dinosaurian forms instead as he thought them more impressive.

In order to protect themselves against Energon surges, the Dynobots required alternate modes covered by a layer of synthetic flesh ; Grimlock refused to transform into Ice Age mammals and made the decision to go with dinosaurian forms instead as he thought them more impressive.

In order to protect themselves against Energon surges, the Dynobots required alternate modes covered by a layer of synthetic flesh ; Grimlock refused to transform into Ice Age mammals and made the decision to go with dinosaur forms instead, as he thought them more impressive.

In order to protect themselves against Energon surges, the Dynobots required alternate modes covered by a layer of synthetic flesh ; Grimlock refused to transform into Ice Age mammals and made the decision to go with dinosaurian forms instead as he thought them more impressive.

He soon regretted this, as Grimlock became more and more tyrannical.

This tale, somewhat concurrent with the Earthforce tales, has Optimus Prime arriving on Earth in response to a distress call from Grimlock.

The Hurricane Mode, in which Grimlock forms the back and arms, is a superb multi-purpose type formation, balancing offense and defense with a shield and rifle ; the Cyclone Mode, with Hightower in the upper body, is a power type form excelling in close-quarters combat, wielding a melee shovel, and shield ; and the Typhoon Mode, with Heavy Load in the topmost position, is his battle type formation, which has high offensive power, with a rifle and shovel.

In 2007, USA Today polled people as to which Transformer they want to appear in the next Transformers film ; Grimlock came in tied for second with Devastator.

")-the reason for this varies from depiction to depiction, with some making it the result of true mental limitations, and others vocal processor damage or a ruse Grimlock perpetrates to allow others to think of him as less intelligent than he actually is.

He is almost invulnerable in his Tyrannosaurus Rex mode as shown with his battle with Megatron due to Megatron's primary weapon, his arm-mounted fusion cannon having little or no effect on Grimlock.

Grimlock developed into a tyrannical ruler who led the Autobots with an iron fist.

When the Autobot Headmasters and Targetmasters arrived from Nebulos, Grimlock refused to recognize the authority of Fortress Maximus and failed to establish an allegiance with his group.

After a short time, Grimlock ( along with Jazz and Bumblebee ) was rebuilt by Ratchet as a Pretender.

Their arrival, and their reviving the fallen Autobots with Nucleon, was an important part of Transformer victory that day, but Optimus Prime once again lost his life, sacrificing himself to destroy Unicron, and once again naming Grimlock as his successor with his dying breath.

Grimlock and the Dinobots were semi-regularly called into action when the Autobots were faced with challenges that required extra strength, such as the Sub-Atlantican invasion of Washington, D. C., or the Decepticons ' control of the TORQ III supercomputer ; with every piece of help he and his troops gave, Grimlock was never slow to add a scathing remark about the inabilities of the Autobots.

Also of note, it seemed that, along with the other Dinobots, Grimlock remained in his Dinosaur mode almost exclusively, rarely changing back to his Robot form.

Later in the year, when Decepticon leader Galvatron had Cybertron infused with function-inverting anti-electrons, a dose of the particles gave Grimlock super-intelligence.

The assistant had assembled these " Primitive " Transformers in the hope that their simple instincts could defeat Primacron's newest creation, Tornedron, but one by one they fell to him, with Grimlock apparently crushed under Trypticon.

In the second episode, Grimlock was again in action, trying to protect Vector Sigma alongside with two fellow Dinobots and Jazz.

The process only barely succeeded, Megatron was deranged and animalistic, and was ultimately defeated by Optimus Prime and Grimlock.

Optimus Prime has also returned to Earth commanding Bumblebee, Cliffjumper, Grimlock, Jetfire, Mirage and Rodimus ( formerly Hot Rod ).

Grimlock can be cold, merciless and contemptuous of those he considers beneath him, such as human beings, and at times, even Autobot leader Optimus Prime himself, who Grimlock would gladly supplant as Autobot leader if he were able to, giving him a superiority complex as indicated by his Generation 1 tech specs.

Grimlock is among the strongest of the Transformers, possibly an equal to, or even superior to Optimus Prime and Megatron in certain continuities.

After a prolonged period living in self-imposed exile, the news of Optimus Prime's death brought Grimlock back to the Autobots.

His policy towards Earth and its inhabitants were vastly different from Optimus Prime's – instead of viewing them as objects of protection, Grimlock expressed a disdain for humanity, viewing them as an inferior species unworthy of their protection.

Subsequently, Fortress Maximus orchestrated the recreation of Optimus Prime as a Powermaster, and Grimlock stepped down as leader.

Grimlock was seen among the Autobots being repaired on the Ark when Optimus Prime sent Landmine and Cloudburst on their mission to obtain computer chips to repair fellow Autobots in issue # 52, " Guess Who The Mechannibals Are Having For Dinner?

Under the leadership of Powermaster Optimus Prime, Grimlock proved to be a loyal and powerful Autobot, daring even to battle the Matrix-powered Decepticon Thunderwing during the Matrix Quest.

Grimlock was one of the few survivors, and when Optimus Prime returned, recreated by the Last Autobot, Grimlock participated in the rout of the Decepticons.

With his transformation capabilities restored ( the explanation for which was not offered in the American series ), Grimlock was Optimus Prime's second in command in the so called Generation 2 series, aiding in the Autobots ' war against the " second generation " of Cybertronians led by Jhiaxus.

In his private thoughts, however, Grimlock considered Optimus Prime too weak to lead, seeking the position for himself.

When Soundwave read his mind and learned of this animosity, Megatron was able to trick Grimlock and the Dinobots into switching sides, attacking and capturing Optimus Prime.

Ultimately, it was when Optimus Prime threw himself into harm's way to save Grimlock from an explosion that he accepted his mistake and rejoined the Autobots.

After getting word from Optimus Prime that Megatron was alive on Earth Grimlock left Ultra Magnus in charge of the Graviton and took a shuttle to Earth.

In the story Crossing Over by Fun Publications Grimlock was among Autobot troops of Optimus Prime who responded to the sighting of Megatron and arrived in time to save the dimensional traveling Autobot Skyfall from Megatron's wraith.

Omega was present when Grimlock and Blaster battled for leadership of the Autobots, and later, after Optimus Prime's return, was part of the force that was attacked by the two Decepticon factions under Ratbat and Scorponok, being taken out by Buzzsaw.

When he ran into the Autobot platoon under Optimus and Grimlock, he captured them alive with intent to convince them to join the Empire, and when they rebelled he pursued them with intent to destroy.

Optimus Primal found himself teamed up with War Within Grimlock and Armada Megatron in rescuing captive Cybertronians from Unicron.