You gain a +2 bonus to attack rolls and damage rolls made with this magic weapon.
The weapon has 1d8 + 1 charges. When you attack a creature that has fewer than 100 Hit Points with this weapon and roll a 20 on the d20 for the attack roll, the creature must succeed on a DC 15 Constitution saving throw or be slain instantly as the sword tears its life force from its body. Constructs and Undead succeed on the save automatically. The weapon loses 1 charge if the creature is slain. When the weapon has no charges remaining, it loses this property.
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.
If a weapon has the Thrown property, you can throw the weapon to make a ranged attack, and you can draw that weapon as part of the attack. If the weapon is a Melee weapon, use the same ability modifier for the attack and damage rolls that you use for a melee attack with that weapon.
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.