A/N: This bit was greatly inspired/clarified by the Shortpacked! comic page of July 20, 2011. You can find it online.
TFTM: Retribution
He felt them die. As it did each time a spark from either faction was extinguished, the Matrix flared within him, leaving echoes of each bot's unique energy etched like shadows on the walls of his mind. He felt them all die: Ratchet, Prowl, Brawn.
Ironhide.
He rose with grim determination. "I'm going to need another shuttle," he said.
"No more, Optimus Prime! Grant me mercy, I beg of you!"
"You who are without mercy now plead for it? I thought you were made of sterner stuff."
The Decepticon's hand twitched, and Prime fired instantly: a shot meant to wound, not kill. He didn't trust Megatron for an instant. The blast knocked Megatron's arm loose from its socket, so that it hung useless from his shoulder joint.
Megatron glared up at him as he approached cautiously.
"There's a pistol hidden behind that rock!" yelped Hot Rod, and made as if to dive into the fray to save Prime.
The red Commander barked a sharp order. "Stay back, Hot Rod. This is my fight."
But even as he spoke, the gray Decepticon made a grab for the hidden pistol. He was fast, and he was subtle.
But Prime was faster. Megatron's lifeless body collapsed slowly to the ground, a smoking ruin where its head had been.
"That's for my friends, you spawn of a glitch," the Autobot said grimly.
"Gather up the troops," he told Hot Rod. "We end this now."
((It's dark, and maybe too dark for Prime. But boy did it feel good!))