Sword of Wounding +1

(Requires Attunements)
Once per turn, when you hit a creature with an
Attack using this Weapon, you can
wound the target. At the start of each of the
wounded creature's
turns, it takes 1d4 necrotic damage for each
time you’ve wounded it, and it can then make a
DC 15 Constitution saving throw, ending
the effect of all such wounds on itself on a success.