Shortsword of Life Stealing

When you attack a creature with this magic weapon and roll a 20 on the d20 for the attack roll, that target takes an extra 15 Necrotic damage if it isn't a Construct or an Undead, and you gain Temporary Hit Points equal to the amount of Necrotic damage taken.

Vex (Mastery): If you hit a creature with this weapon and deal damage to the creature, you have Advantage on your next attack roll against that creature before the end of your next turn.

Finesse: 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.

Light: 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.

Proficiency: martial, shortsword Source: Dungeon Master's Guide (2024) p. 314