Heart of Azgar is a Unique Chest Armor in Diablo IV Season 15. It comes from World drop (any difficulty, drop rate scales with Torment tier); Dedicated drop: The Butcher (Greater Lair Boss, Gea Kul, Torment 1+; Boss Trophy: Fresh Meat); Horadric Cube: Item Transmutation (Amalgamation) - 5x Fresh Meat (Boss Trophy) rolls a Unique from this boss's pool; can roll Mythic quality with the 'Crafted' tag.
Unique power
When you hit at least 1 enemy with Maul, increase its Attack Speed by +3% and damage by [20-25%][x] for 5 seconds, stacking up to 5 times.
Affixes
+[1-3] to Basic Maul Skills (1-3)
Where it drops
World drop (any difficulty, drop rate scales with Torment tier)
Dedicated drop: The Butcher (Greater Lair Boss, Gea Kul, Torment 1+; Boss Trophy: Fresh Meat)
Horadric Cube: Item Transmutation (Amalgamation) - 5x Fresh Meat (Boss Trophy) rolls a Unique from this boss's pool; can roll Mythic quality with the 'Crafted' tag
Horadric Cube: Item Transmutation (Upgrade to Unique) - Common item of the same slot + 1 Enhanced Primordial Dust + 10 Primordial Dust (random Unique of that slot)