A stubborn and hot-headed Autobot, Grimlock was the leader of the Lightning Strike Coalition until he was fundamentally changed by the Decepticon scientist Shockwave turning him into something more bestial- a Dinobot.
Uniend 911.05 Alpha (Aligned)
As the war on Cybertron escalated, Grimlock, the leader of the Lightning Strike Coalition sub-faction of the Autobots, sent his subordinate Swoop ahead to find where the Decepticons were getting their energy. Optimus Prime put Grimlock's forces on the front line to hold the line against the Decepticons at Iacon. Eventually, Grimlock grew tired of holding the line and led an incursion into the Decepticon lines. Prime ordered Grimlock to fall back and Grimlock reluctantly followed orders. Grimlock met with Prime where Grimlock criticized his superior and provided him a record of the battle to find new strategies.
Later, Grimlock was notified by Perceptor that he had a call from Swoop. Swoop reported that he found how the Decepticons were getting their Energon before the transmission cut off. In response, Grimlock decided to move out to help him.
- The Transformers: Fall of Cybertron #1- Good Intentions