Heart of Azeroth Essence
Essences add a whole new layer to the Heart of Azeroth system, in addition to the Azerite Armor that you already have.
Each Essence has both Major (generally active) and Minor (passive) abilities. Upon completing the initial quest from Magni, you’ll open a single Major slot in the Heart of Azeroth. Placing an Essence in the Major slot grants you that Essence’s Major active ability, which is added to your Spellbook. You’ll also gain the benefit of any Minor passive abilities from the Essence.
There are also two additional Minor slots in the Heart of Azeroth that will activate the Minor (passive) abilities of any Essences added to them. The first Minor slot will become available at Heart of Azeroth level 55, and the second Minor slot will become available at Heart of Azeroth level 65. The Heart Forge lets players infuse their Heart of Azeroth with Essences to grant new combat-related powers. Once you’ve collected a new Essence - obtained by participating in a wide variety of content - you’ll head to the Heart Forge to infuse your Heart of Azeroth with it, “learning” the Essence and permanently adding it to your collection. Much like Talents, once you’ve learned an Essence, you’ll be able to apply it or swap it out through a new Heart of Azeroth interface within rest areas, cities, or when using items such as the Tome of Quiet Mind.