Energon-axe

The energon-axe is an iconic weapon used by Optimus Prime whenever he needs a melee weapon. He retracts his hand, and an emitter for the energy axe projects the blade. Prime first used it on Earth when he and Megatron fought on a particular dam, and it is a very memorable ability. Other Transformers are also known to use energon-axes in combat.

More than Meets the Eye
When duelling Megatron on top of Sherman Dam, Optimus Prime used his energon-axe against the Decepticon's energon mace. Prime lost the fight when he was distracted by Spike Witwicky calling for help.

Prominant users of Energon-axes

 * Optimus Prime
 * Wreck-Gar