Corpse Slayer Rapier

You gain a +1 bonus to attack and damage rolls made with this magic weapon. When you hit an undead creature with an attack using this weapon, the attack deals an extra 1d8 damage of the weapon's type, and the creature has disadvantage on saving throws against effects that turn undead until the start of your next turn.

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.

Proficiency: martial, rapier Source: Explorer's Guide to Wildemount p. 266 (Third Party), Player's Handbook (2014) p. 149