Transformers - Tempus Exitium
When Motormaster booms out orders in his hollow, bottomless-deep voice of doom, his Stunticon soldiers listen in very real fear. A cold and brutal tyrant, without an ounce of mercy or care for any lesser being, he considers himself the true “King of the Road.” He longs to one day prove his claim by destroying Optimus Prime in a head-on collision, though he fears that someone else might kill Prime before he can. His fellow Stunticons hate him, but are too terrified of him to dare disobey his orders.
? BCE (Before the Great War)
Megatron Origin 3 – Motormaster is seen going to a secret location where Megatron will give a speech and starts forming the Decepticons. Unfortunatly, the Autobots know the location, and attack, imprisoning as many of the gladiators as possible. Motormaster ends up in a cell in the Kaon Autobot Security HQ with Megatron and Starscream. Right after Starscream talks to a guard, Megatron screams traitor, and orders Starscream killed. Before the job can be done, Starscream is removed from the cell.
Megatron Origin 4 – Motormaster tried to prevent Sentinel Prime from getting his Apex Armor. He failed. Miserably.