World of Warcraft had a problem for most of it’s time since release. Once you reached the level cap, you geared up through Heroic Dungeons as fast as possible and went raiding. One your gear outstripped the loot, you forgot all about them and never set foot inside for the rest of the expansion. That was a good chunk of the content just sitting there, unused.
In this new expansion, Blizzard is trying to fix that. While World Quests, introduced in World of Warcraft: Legion, are somewhat similar to Bounties found in Diablo III: Reaper of Souls, Mythic+ Dungeons are similar to Greater Rifts, found in the same game. The idea of Greater Rifts is that when you complete a, let’s say, Tier 25 of a Greater Rift, you gain access to Tier 27, which has slightly harder enemies and offers better rewards. In theory, Greater Rifts scale endlessly, always offering you a challenge if you want it.
That’s precisely how Mythic+ Dungeons are going to work, at least in essence. Once you complete a Mythic (NOT Mythic+) Dungeon, you get a Keystone. If you successfully complete the Mythic+ within the time limit, it will get upgraded to a higher difficulty and send you to another Dungeon. Your loot scales with the Dungeon difficulty. Also, the faster you complete it, the more loot chests you will get at the end, up to three. If you fail the dungeon, you will still get one loot chest at the end, but your keystone will be “depleted”, not giving you any loot for any other Mythic+ you complete using it. I’m not entirely sure at this point in time, but it might be that if you do manage to complete the same dungeon from the depleted keystone, it will get upgraded again and you will be able to go on using it. I also looks to be true that you will be able to enter a Mythic+ dungeon created by someone else, getting loot if you complete it. Without affecting your own keystones. If that’s true, groups might be be able to farm with all five keystones in a group.
Your keystone for Mythic+ has a week-long lockout, similar to raids. When the lockout is reset on Tuesday (for NA) and Wednesday (for EU), your keystone will be destroyed and you will receive a chest with a piece of loot in your Class Hall. The iLevel of the item will depend on the tier of the highest Mythic+ you completed successfully. Take it with a grain of salt because it still might change, but I believe that that the base iLevel of gear that drops in Mythic Dungeons is 840. With Mythic+, you will get additional 5 iLevels for each “tier” you complete. For example, if you had a level 6 keystone at the end of the week, it would mean that you completed level 5, which should give you an item of iLevel 865. Also, you should get a keystone which is of slightly inferior level to the one you had when the week’s lockout was over. That’s done to encourage you to level it up once again, but avoiding making you to go through content you massively outgear in order to reach the level that is suitable for your gear and skill.
What this means for World of Warcraft: Legion is quite simple. Raids won’t be the only way for you to progress anymore. If you can find a small group of people you like to play with, you can progress through the Mythic+ system, to deck yourself out in raid-level gear. Higher tier Mythic+ Dungeons won’t be easy, however, because at level 4, 7, and 10. Dungeons with a level higher than that will have random effects added to them. So, level 5 will have 1 extra effect, level 8 will have 2, and 11 will have 3, supposedly.