You were Orion's friend, until you inadvertently killed him. You dropped his body into a bottomless pit, then killed Sentinel Prime in a fit of rage, and you were ready to take over Cybertron, until something rose from that pit. It wasn't Orion. Orion was no more. He was made into Optimus Prime. You attacked him, but after fighting a lengthy battle, he destroyed your weapons, and left you lying on the ground in defeat. He looks down at you, as he begins speaking.

"We were given the power to change our world, and you chose to destroy it, just like Sentinel. You have betrayed Cybertron and it's citizens."

He says, as he lets his face mask sheath back, showing his face as he speaks in a shaky tone.

"And you betrayed me..."