Kyshaarth's Fang 2014
Weapon, rare, (requires attunement)
This dagger's blade is composed of black, bone-like material. Tales suggest the weapon is fashioned from a Voidling's (see Tome of Beasts) tendril barb. When you hit with an attack using this magic weapon, the target takes an extra 2d6 necrotic damage. If you are in dim light or darkness, you regain a number of hit points equal to half the necrotic damage dealt.
Properties
Finesse
When making an attack with a finesse weapon, you use your choice of your Strength or Dexterity modifier for the attack and damage rolls. You must use the same modifier for both rolls.
Light
A light weapon is small and easy to handle, making it ideal for use when fighting with two weapons.
Thrown (range 20/60)
If a weapon has the thrown property, you can throw the weapon to make a ranged attack. If the weapon is a melee weapon, you use the same ability modifier for that attack roll and damage roll that you would use for a melee attack with the weapon. For example, if you throw a handaxe, you use your Strength, but if you throw a dagger, you can use either your Strength or your Dexterity, since the dagger has the finesse property.
Source: Vault of Magic (Kobold Press) · License: OPEN GAME LICENSE Version 1.0a details