At the end of Legion, the titan Sargeras was imprisoned, but not before he plunged his sword into the planet Azeroth. This not only devastated a massive area (much of the desert zone of Silithus is now cracked and scorched), but badly wounded the gestating titan inside. While the heroes managed to ablate the worst of the damage (at the cost of the majority of their artifact weapons' mythic power), the world is still wounded and bleeding a substance called "Azerite," which has great magical potential. The Horde Warchief, Sylvanas Windrunner, attempts to consolidate Horde power on Kalimdor and gain a monopoly on Azerite (which is primarily found at the southern end of the continent). Her campaign to do so, the War of Thorns, formed a pre-launch event for the expansion and ends with the major Night Elf holdings on the continent seized or (in the case of their capital city of Darnassus) annihilated. The Alliance makes a retaliatory strike against her home base, the Undercity, which was formerly the human capital of Lordaeron. This succeeds in driving the Horde out, but before leaving Sylvanas saturates the area with disease and toxins that render it uninhabitable. With this tit-for-tat military exchange, the Horde has almost complete control over Kalimdor, while the Alliance has near-total dominion over the Eastern Kingdoms. With further conflict inevitable, Battle for Azeroth takes the two factions to the continents of Kul Tiras and Zandalar to recruit new allies in order to turn the tides of war.
The bones of Mythic+ are fairly simple, but it’s that simplicity that makes it Battle for Azeroth’s most rewarding mode. It’s fun, generally only takes about 40 minutes per dungeon and allows small groups of players to push themselves exactly as hard as they’d like. Battle for Azeroth’s dungeons are extremely well-designed and consistently entertaining, even after doing some of them 20-plus times, which makes the challenge of Mythic+ a great way to keep people playing.
As with Jewelcrafting, Alchemy is a bit more nuanced than looking at hourly rates. Flasks will provide you with a good baseline, but if you carefully watch the market and plan your transmutes with market trends, you could see huge gains like JC. Assuming you are focusing only on selling Flasks, you will make around 2138 gold/hour if you are also an Herbalist.
Mythic+ rewards will also go up by 30 item levels; however, during the first week of Season 2, rewards from end-of-run chests will be capped at Mythic 6 quality (item level 385), and the chest you open next week will contain Season 1 rewards if you do a Mythic+ run this week. (So, for example, if you do a Mythic 10 during the final week of Season 1, you’ll get a Season 1 item level 380 piece and 60 Residuum from your first Season 2 chest.)