S3·E30 The Return of Optimus Prime (2)

Optimus Prime is back and leads a team to Charr to retrieve the ship alloy from Galvatron. Galvatron guides them to it's location, but they confront a couple dangers and must fend off infected Transformers. Optimus and SkyLynx are the only ones not infected and barely get away with the alloy. The alloy is used to safeguard Optimus from the Hate Plague for his battle against Rodimus as the Matrix is the key to the cure.