The black blade of this sword is crafted from a mysterious arcane alloy. You gain a +1 bonus to attack and damage rolls made with this magic weapon. While the sword is on your person, you are immune to effects that turn undead.
While holding the sword, you can use an action to give yourself 1d4 + 4 temporary hit points. This property can't be used again until the next dusk.
When you hit a creature with an attack using this weapon, you can fill the target with unsettling dread: the target has disadvantage on the next saving throw it makes before the end of your next turn. The creature ignores this effect if it's immune to the frightened condition. Once you use this property, you can't do so again until the next dusk.
When making an attack with a Finesse weapon, use your choice of your Strength or Dexterity modifier for the attack and damage rolls. You must use the same modifier for both rolls.
When you take the Attack action on your turn and attack with a Light weapon, you can make one extra attack as a Bonus Action later on the same turn. That extra attack must be made with a different Light weapon, and you don't add your ability modifier to the extra attack's damage unless that modifier is negative. For example, you can attack with a Shortsword in one hand and a Dagger in the other using the Attack action and a Bonus Action, but you don't add your Strength or Dexterity modifier to the damage roll of the Bonus Action unless that modifier is negative.
When you make the extra attack of the Light property, you can make it as part of the Attack action instead of as a Bonus Action. You can make this extra attack only once per turn.