The Doomstick

The Doomstick is a weapon that appears to be a large naval blunderbuss, however, it is functionally closer to a breech loading shotgun. It is loaded each use with a single shell by opening the breech. Once loaded, the breech cannot be re-opened until the gun has been fired. A simple spring loaded hammer must be drawn back and the trigger squeezed for the gun to fire. Pulling the trigger without drawing the hammer back will not result in anything. Once fired, the breech must be opened manually by the user in order to eject any spent or failed shells before the gun can be reloaded and fired again. 
Each time the gun is opened, whether for reloading or cleaning, all previous items or entities created by the gun vanish. Effects on the characters or enemies such as injuries or status effects remain. Shells can be crafted once per day via ritual that takes 1 hour to complete. Shells have a volatile shelf life and may expire prior to their use. Gun may be used as long as there is ammunition for it. If no ammunition is present, the gun can be used as a blunt weapon like a club, or used as a focus for lesser spells. The chamber and barrel of the gun cannot burst, though the firing mechanism may jam. Gun will not function underwater. The weapon is fitted with a safety latch hidden within the ornate metalwork decorating the stock and its location is known only to its creator, making the gun difficult for others to operate. It cannot be modified to have more barrels or function in any other aspect aside from single action.
HISTORY
The Doomstick began as a simple naval blunderbuss, stowed aboard one of the many merchant ships plying the seas of Avalon. After a brief engagement in repelling a goblin raiding party, the stock had broken after its initial owner used it as a club when out of ammunition. The weapon was offloaded for repairs while the ship was in port, but the courier tasked with its delivery to the armory was found burned to death under a nearby pier shortly after receiving the parts. The broken weapon was not among the remains. Local authorities detected traces of the chemical "Accelerol" on the body, a highly flammable substance often used as fuel. The weapon was deemed to have been destroyed as the flames from an Accelerol fire would have damaged it beyond repair.
The shattered weapon was transported to the workshop of Digs the Kobold. The workshop itself was concealed beneath the port city, with a hidden entrance dug into the rock at the shorebreak. Digs had spent 200 years honing his craft and expertly repaired the weapon using stolen parts and practiced hands, transforming the standard blunderbuss into a weapon of great and chaotic power. 
Over the course of the next few months, the port was home to multiple unexplained occurrences. Massive conflagrations that were somehow extinguished before the fire brigade could arrive. Small vessels had their hulls shot full of gaping holes while docked, but the source of which was never found. Large clouds of smoke and fog that dissipated as quickly as they had appeared. Odd piles of leaves and brightly colored feathers appearing, only to vanish once gathered. Digs had made the shipyard his testing ground, wreaking havoc as he perfected the weapon's capabilities. Digs decorated the weapon with draconic runes and ornate metalwork, making the weapon worthy of such a proud and magnificent creator.