Shadow Mantle

Surrounds your target causing 75 - 112 + 93% weapon damage and reducing their ability to heal by 25% for a duration scaling by pips spent. 1 pip: 7 seconds \n2 pips: 10 seconds\n3 pips: 13 seconds \n4 pips: 16 seconds\n5 pips: 19 seconds.
Comes from Black Mask rune.