. . "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."@en . . "Energon-axe"@en . . . . . . . "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."@en .