Optimus's Machine Gun

After being upgraded to a new body, Optimus Prime obtained a new machine gun which served as his primary weapon for Season 3 of Transformers: Prime.

History
In Rebellion, Optimus used the weapon to a devastating effect on a group of Vehicons upon his return.

In Deadlock, Megatron kicked Optimus's machine gun off the Omega Lock.

Trivia

 * Optimus's mini gun was not seen in Predacons Rising. It is presumed to be destroyed or lost.