After learning the schematics of the revolver used by Willus Zorach around the turn of the sixth century EC, Gumillia crafted the magically-enhanced firearm and employed it as a Justea investigator for the World Police. Following her arrest on November 17, EC 609, the weapon was confiscated by the Torture Department. It was retrieved by Hob Homer shortly after and returned to Gumillia just prior to her escape from prison with Elluka Clockworker. The mage continued to carry it during her journey into and later from Père Noël.
The fireworks gun was a versatile firearm. Based on the original Leviantan revolver model employed by Willus Zorach, the gun was smaller than the average model, making it light to carry and simple to aim. Despite this, its unique matchlock gave it a strong firepower; as a result, the weapon also made a unique sound when fired. making it easy identify from other revolvers. The weapon's firepower could also be further enhanced by inscription runes being carved into its frame.
The weapon itself was able to shoot regular lead bullets as well as magically-imbued bullets. Like standard revolvers, the lead bullets fired could seriously injure or kill a human target. In contrast, the magic bullets produced bright "flashes" that launched a tremendous amount of force. Additionally, the magic bullets could cause large damage to property or incapacitate a target. The flashes' potency varied depending on the settings and magic power inputted into the shot. When given enough power, the flashes and were capable of killing the target.
- The fireworks gun was a more advanced version of the original magically-enhanced handgun Gumillia utilized up through the Jakoku Civil War.
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