Entropic Bone Quarterstaff (5e Equipment)

Weapon (quarterstaff), uncommon (requires attunement by a fighter, monk, or wizard)

This quarterstaff appears to be a length of bone shaped into a staff with quartz runes embedded in rings at the ends. This weapon deals an additional 1d6 necrotic damage. Once per day, you may use your reaction to make an attack roll against you or a creature within 5 feet of you be made with disadvantage.