Bàs Crith (Trembling Death)

You have a +1 bonus to attack and damage rolls made with this magic weapon.

This is a very normal looking sword save for its name being etched into the blade.

The first time you attack with the sword on each of your turns, the sword trembles in your hand allowing it to easily cut through the armor worn by your foes. If the creature you are attacking is wearing any non-natural armor you gain an additional +2 to the attack roll

Once attuned to the blade the wielder has a strong feeling they are missing something. They slowly come to realize they need to find this sword's sister blade(Beatha Crith), as well as a general idea where it can be found. If both swords are attuned and both make a successful hit on the same turn you can use your bonus action to attack any creatures of your choice within 5ft of you (This requires an attack role against each creature). You are infused with energy from the swords performing a whirling dervish of attacks around yourself dealing 5d4 damage on each successful hit.

Proficiency with a Shortsword allows you to add your proficiency bonus to the attack roll for any attack you make with it.

Notes: Bonus: Magic, Damage, Combat, Finesse, Light, Vex