The Unmaker is a Unique Helm in Diablo IV Season 15. It comes from Random world drop / any Lair Boss (one guide: 'drops at any Difficulty Tier, increased drop rate per Torment tier'); 3.2.1: all Uniques drop from level 1 in any Difficulty; targetable via Horadric Cube reroll.
Unique power
Soulrift's duration is increased by 0.5 seconds for every 30 Essence you spend while it's active, up to 8 seconds. Soulrift deals [300 - 350]% (3.2.1: increased from 200-250%) of its Shadow damage per second to surrounding enemies for every 30 Essence you gain while it's active.
Affixes
+3.0-8.0% Cooldown Reduction
Where it drops
Random world drop / any Lair Boss (one guide: 'drops at any Difficulty Tier, increased drop rate per Torment tier'); 3.2.1: all Uniques drop from level 1 in any Difficulty; targetable via Horadric Cube reroll