A large shotgun with 3 revolving barrels, each having glowing runes that are primary colors. Each barrel has its own unique damage type and reactivity. At the start of each combat round, the player rolls a d6 as he spins the barrel.

1-2 RED Barrel - Launches a Small, volitile, glowing red orb  that hovers at its destination before exploding, dealing 3d6 fire damage in a 15ft radius. DEX Save 16

3-4 BLUE Barrel - Shoots out a lightning bolt. If the bolt hits the first target, it has a 75% chance(5-20 on a d20) to chain to another target. If the 2nd target is hit, the bolt has a 50% chance(10-20 on a d20) to chain a second time. Each hit takes 2d8 lightning damage

5-6 YELLOW Barrel - Shoots out a tiny black orb that transforms into a wormhole that pulls enemies hit in a 15ft radius toward the singularity, and dealing 1d10 force damage to enemies hit. Con save 16

Also, when hit with a melee attack, you can use you reaction to get 15ft of movement, without provoking attacks of opportunity 5 times per long rest.

The Item cannot be removed from you in any way. If removed by an means, it will teleport back to the owner and spin its barrels, auto shooting whatever barrel it lands on.

Firearms are a new and volatile technology, and as such bring their own unique set of weapon properties. Some properties are followed by a number, and this number signifies an element of that property (outlined below). These properties replace the optional ones presented in the Dungeon Master’s Guide. Firearms are ranged weapons.

Reload. The weapon can be fired a number of times equal to its Reload score before you must spend 1 attack or 1 action to reload. You must have one free hand to reload a firearm.

Misfire. Whenever you make an attack roll with a firearm, and the dice roll is equal to or lower than the weapon’s Misfire score, the weapon misfires. The attack misses, and the weapon cannot be used again until you spend an action to try and repair it. To repair your firearm, you must make a successful Tinker’s Tools check (DC equal to 8 + misfire score). If your check fails, the weapon is broken and must be mended out of combat at a quarter of the cost of the firearm. Creatures who use a firearm without being proficient increase the weapon’s misfire score by 1.

Explosive. Upon a hit, everything within 5 ft of the target must make a Dexterity saving throw (DC equal to 8 + your proficiency bonus + your Dexterity modifier) or suffer 1d8 fire damage. If the weapon misses, the ammunition fails to detonate, or bounces away harmlessly before doing so.

Ammunition

All firearms require ammunition to make an attack, and due to their rare nature, ammunition may be near impossible to find or purchase. However, if materials are gathered, you can craft ammunition yourself using your Tinker’s Tools at half the cost. Each firearm uses its own unique ammunition and is generally sold or crafted in batches listed below next to the price.

THIS IS UNOFFICIAL MATERIAL

These game mechanics are usable in your campaign if your DM allows them but not refined by final game design and editing. They aren’t officially part of the Dungeons & Dragons game and aren’t permitted in D&D Adventurers League events unless otherwise stated.

Notes: Sense: Blindsight, Set: Speed (Walking), Deafened, Reload, Misfire