When Antorus the Burning Throne raid opened, the Wakening Essences became available for players to collect. These items act as a currency, and by getting 50 of them, you can upgrade 1 Legendary item to ilvl 1000! You are able to earn up to 175 Essences per week, so you can pretty easily upgrade 3 Legendary items per week.
In order to get the Wakening Essences, you need to do the following actions:
- Mythic+ Dungeons. you get 20 Wakening Essences from the Weekly Chest. The difficulty of the Mythic+ does not matter.
- Antorus bosses. Any boss in the Antorus raid will drop 3 to 6 Essences per boss! It does not matter if you kill the boss on LFR, normal, heroic or Mythic! Any kill give you the same amount, but you will only get Essences on the first kill on any difficulty each week.
- Emissary caches. Each Emissary cache will contain between 5 and 10 Wakening Essences. You should definitely do these every day if you want to upgrade your Legendary items!
- Daily Legion Heroic. You get 5 Wakening Essences when you complete the first Legion Heroic dungeon of the day. This totals up to 35 each week if you are able to do it every day.
- Weekly PvP Quests. If you gain 1,500 honor in either 2s, 3s or rated battleground, you get 7 Wakening Essences. This means that you get 21 additional Wakening Essences by PvPing if you do all 3.
There is no other way to obtain Wakening Essences at the moment, so most players will get just over 100 each week by playing PvE. The fastest way to grind them would be to do all the actions above daily and weekly, but casual players should stick to running Antorus on LFR difficulty while doing Emissary Quests and daily Legion Heroic dungeons.