Veil of Death

For the next minute, you are enveloped in a shadowy aura that grants you resistance to all damage except radiant. Your attacks and spells deal an extra 2d10 necrotic damage.  When the effect ends, you lose 2d10 hit points as the shadows drain you of vitality, leaving you fatigued. If your hit points drop to 0 from this effect, you fall unconscious but remain stable. Once per long rest