Astral Slayer

Astral Slayer.
Found by a crashed spell jammer inside a box with an emblem resembling a cog the only data pretraining to the origin of these weapons seems to be lost to the void
When used to make a ranged attack you inflict 3d8 + your Intelligence modifier. lighting damage and once per day the target must succeeded a DC 15 dexterity saving throw or be frightened until the end of the targets next turn.

Chain-Blade. You create a matching blade to accompany your firearm, rendering you a deadly opponent in both melee and ranged combat. Being within 5 feet of a hostile creature doesn’t impose disadvantage on your ranged attack rolls. Additionally, when you use your action to shoot, you can use your bonus action to strike at a creature within melee range. Make a melee attack roll. The attack roll uses your Intelligence modifier, and you are proficient with the attack. On a hit, the attack deals slashing damage equal to 3d8 + your Intelligence modifier.

Misfire (3). 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.

Curse. This pistol is cursed, and becoming attuned to it extends the curse to you. Until the curse is broken with Remove curse or similar magic, you are unwilling to part with the pistol, keeping it within reach at all times. And when the weapon misfires the chain-blade dislodges dealing 3d8 + your Intelligence modifier to a random creature within 60ft

It’s up to you to decide whether a character has proficiency with a firearm. Characters in most D&D worlds wouldn’t have such proficiency. During their downtime, characters can use the training rules in the Player’s Handbook to acquire proficiency, assuming that they have enough ammunition to keep the weapons working while mastering their use.

Notes: Replace Damage Type: Lightning, Melee Weapon Attack: Slashing, Frightened, Artificer, Damage, Combat, Cursed, Range, Two-Handed, Ammunition (Firearms), Reload, Slow