Transformers: Dark of the Moon
(2011)
Sentinel Prime had made a deal with Megatron to use the pillars to transport Cybertron into Earth's atmosphere. Sentinel kills Ironhide. As Shockwave's forces invade Earth, Sentinel states the Megatron will never rule him.
In the final battle, American troops manage to incapacitate Shockwave, allowing Optimus and the wreckers to finish him off. Sam kills Starscream using Que's specially designed Cybertronian human weapons. Carly pep-talks Megatron into betraying Sentinel. With Sentinel incapacitated, and Optimus Prime with just one arm, Megatron taunts Optimus. Optimus attacks, decapitates Megatron with his trademark axe, and then finishes the job on Sentinel. Sam pushes Dylan into the control pillar being controlled by Sentinel, electrocuting him. Bumblebee destroys the pillar. With no more space bridge, an incomplete Cybertron vanishes into a black hole. The world is safe forever.
Body count:
Fun fact: Leonard Nimoy, who voices Sentinel Prime, also did the voice of Galvatron for 1986's Transformers The Movie
Thanks Herbmeistr!