Mythic+ are a step-above regular mythic dungeons. Similar to Greater Rifts in diablo mythic+ uses keystones that will increase mobs health and damage and add new abilities(affixes) based on the level of the keystone. The higher the keystone, the better the rewards! Want to know more about mythic+ dungeons!? Click here.
These dungeons get extremely difficult the higher you get. Our professionals have run these dungeons thousands of times to clear these effortlessly.