Can always use more crests!
Mythic+ Dungeons
For players who still have the means, Mythic+ dungeons remain the best way to earn Myth Dawncrests, awarding 10-16 crests between key levels 9-12. With each dungeon taking around 20-40 minutes, that's roughly one crest every two minutes. Although Mythic raids are also an effective way of earning these crests, they require a lot more players and coordination that isn't always puggable on a whim, while Mythic+ dungeons can be run at virtually any time and as many times as a player is willing to go.
In terms of which Mythic+ dungeons to run, most players tend to prefer Pit of Saron. This seems to be the dungeon that you can speedrun when you're overgeared, though Nexus Point Xenas is also a good option. You will want to avoid dungeons that have RP or dangerous mobs that can prevent you from pulling multiple groups together at a time. Al'gethar is a great example of a dungeon that it's the best as when you get to Crawth, you have to kill 3 waves of birds solo, and a Guardian Sentry.
Farming Myth Crests are going to be easiest in a 5 man pre-made group as that not only cuts out the timing of queues, but also allows you to reroll keys to get the better dungeons that you want. You also get to choose the people in your group, allowing you to
Ritual Sites
Once Patch 12.0.7 arrives, Tier 6 Ritual Sites also become a repeatable Myth crest farm, awarding five for each completion. Though T11 Delves currently award the same five crests upon reaching Rank 4 on its renown track, players may only earn that reward four times per week, while T6 Ritual Sites award 5 Myth Crests per run with no limits or lockout.
In addition to the normal rewards, players will also earn a small amount of Myth Dawncrest.
Completed in half the time or less than a typical Mythic+ dungeon, these ritual sites can be very efficient grind, but are even more important for solo players, who do not otherwise have much access to Myth-track gear. For them, crafting is the real endgame, and giving them a source of repeatable Myth crests dramatically speeds up their ability to earn endgame gear beyond what they get from completing Delves and Nullaeus each week.
Normally, this counts against the weekly crest cap, but that isn't an issue anymore.
The Daggerspire Point Ritual Site is likely the faster option of the two as there's a lot less trash that is in your way.
Trading Up Crests
The final option is to uptrade 30 Hero Dawncrest into 10 Myth ones. While it isn't particularly efficient to farm three times as many Hero crests, it is useful for players who have outgrown their use, as well as those who have a harder time completing group content to earning Myth crests directly. Hero crests are largely earned in the same way, but generally more plentiful and easier to get, so this can be a great way to get those last few crests in order to upgrade something before raid.
