Silver Sword is the signature weapon of the notorious bounty hunter Shining Armour. For quite some time, Shining has plagued the area around Red Light as a bounty hunter and mercenary, willing to take any kind of work and kill anyone for the right price.
Silver Sword became Shining's most recognizable weapon, people who didn't recognize Shining were bound to recognize the weapon and know it was him. Silver Sword was used by Shining to assault the Cistern orphanage, he arrived too late to kill any of the orphans but set his eyes on Snakebite as he had never killed an alicorn before. Silver Sword was used against Snakebite and managed to land several shots on him before Shining was distracted by Snakebite's new spell, unkindness of Ravens and killed.
Snakebite went to a hotel/bar to spend the night and became popular after Silver Sword was displayed to the customers as proof of Shining Armour's death. Silver Sword was used again by Snakebite during the initial assault on Red Light, he considered selling the weapon as it is rather large and cumbersome, compared to the smaller arms he uses, like the plasma pistol and Woodcutter.
Silver Sword was wielded by Snakebite during the defense of Red Light, using it to Strafe Zeals forces from the sky.