"it was this blade that ended the Great War and defeated the Titans." (Zeus, God of War 2)
The Blade of Olympus, from God of War. Specifically as featured in GOW2 and GOW3. The Blade was forged by Zeus from the powers of both Heaven and Earth to defeat and banish the Titans into Tartarus. The Blade is then used by Zeus again to trick Kratos into giving away his powers, and continues to hold particular importance until the end of the entire trilogy.
The Blade looks amazing. Notice the head/face shape below the hilt, and the energy rising up through it, then going next to the human shapes above, raising their hands to it as if in prayer. It's a blade that essentially defines the worship of the gods. I've been wanting to do this one for a while!