The Lineage of Primes

Prima, leader of the Original 13 Sons of Primus, handed the Matrix to Prime Nova.

Prime Nova was killed when the Quintessons enslaved Cybertron.

The warrior that became Guardian Prime rose to prominence in the battle to regain Cybertron's sovereignty after a millennia of Quintesson rule.

Guardian Prime was killed by Megatron, announcing the start of the Great War. Sentinel Prime was selected by the Matrix as the new leader.

Upon Sentinel's death, Orion Pax became Optimus Prime.

Optimus Prime died from his injuries in the Battle for Autobot City in 2005 CE.

Hot Rod became Rodimus Prime after wrestling the Matrix from Galvatron within the body of Unicron.

Rodimus handed the Matrix back to Optimus after his return from the Allspark.

Optimus Prime was critically injured in the final battle of the Great War. A Maximal selflessly came to his rescue – the brave action causing the Matrix to pulsate within Prime's chest. Optimus was hauled from the battlefield by Hoist, but not before handing the Matrix to his rescuer, Maxim, transforming him into Maximus Prime – the first Maximal to become a Prime.