Template:Legion legendary source

 drops from dungeon, raid, world bosses, rare elites on the Broken Isles and Argus, and Commanders at Invasion Points. It can also be found in world quest caches, PvP strongboxes, Mythic+ weekly caches, and Blingtron 6000 Gift Package. Lastly, it can also be discovered by using a Relinquished token purchased from Thaumaturge Vashreen.