Energon Swords
Now, Optimus Prime may believe his credo of "Freedom is the right of all sentient beings", but he tends to revoke in the case of the Decepticons. Thus, when entering combat, he uses his Ion Blaster, Barrage Cannon and his Dual Energon Swords their fullest effects. Possesing one of each arm, he charges the swords, also known as battle blades, via a quantum electric generator with a max yeild of 3000 degrees Celsius and a burn rate of five kilojoules per second. In Transformers, while escorting Sam Witwicky and the AllSpark to Mission City, Prime and the Autobots were being followed by Decepticons Barricade and Bonecrusher. They were pretty hot on their trail. Bonecrusher transformed and sneaked up on Prime. Prime then transformed and had a brief fight with Bonecrusher, throwing the Decepticon so hard off an overpass that one of his optics popped out. Before Bonecrusher's death, Prime ripped his arm off, making Bonecrusher as mad as hell. Partially blind, Bonecrusher tried to attack Prime but the Autobot leader, but Prime was ready, and jabbed his sword into Bonecrusher's neck, decapitating him. In Revenge of the Fallen, while protecting Sam Witwicky, Optimus Prime was forced to a three-on-one battle with Starscream, Grindor, and Megatron. That's excatly when Prime pulled out his swords. He managed to rip Grindor's face in half. Later, after Prime was resurrected by the Matrix of Leadership and received parts from Jetfire, he worked his way through the floating debris and with one shot at the Solar Harvester, he destroyed it. Later on ground, Prime sliced off Megatron's Fusion Cannon and sliced The Fallen's chin off, then proceeded to rip the The Fallen's face off with his own staff.
Prime Blade Wielding

Swiss Army Prime.