Sliver of Midnight (5e Equipment)
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Weapon (Shortsword), artifact
This weapon was originally made by a mysterious group of elven assassins who answered to a strange and old deity of shadows and murder, one whose symbol was in fact a rose. It was said they worked in secret for thousands of years killing anyone who would pray to their ancient mistress and in return they expected payment, with hidden sanctuaries in places like old caves, basements, even abandoned towns they worked and commanded many cruel and cold killers with no target to young or old, too rich or too poor, for the right price.
The sliver of Midnight is a small short sword that is similar in design to a saber with a thin blade and silver engravings depicting a rose blossoming in a field of fallen warriors. its handle is a strange felt-like, black material that is rather pleasant to hold and has a rather small guard, merely a rose-bud shaped guard that the blade comes out of.
Unseen Shadow You have advantage on Dexterity(Stealth) and have the ability to cast the spell Invisibility on yourself once per short rest.
Midnight Strike When you attack an enemy you deal 1d8 Posion damage, unless you strike unseen in which case you deal 2d8 cold damage and strike with advantage.
The Poison of the Moon You may use an action to apply poison from a small hidden compartment on the handle to the blade of the short sword, it will now deal 1d6 poison damage on top of what it'd normally deal.
Destruction You may destroy this weapon in one of two ways, one like any other weapon a skilled blacksmith can have this blade in ingots in an amount of time that is dependent on the smithy's skill, however in 2-3 weeks the ingots will melt upon themselves and reform the weapon, so this only works for that much time. Two, or the more productive way, is to sacrifice to a God or Goddess of death, this'd be pretty simple as you just have to locate a Cult willing to do that (assuming you don't want to be associated with death deities and sacrifice) or to locate an avatar of this deity and make them take it, as to whether or not they would want it is of course up in the air as no one has tried it before.