XP Potions: The Elixir of Rapid Mind and Elixir of Ancient Knowledge no longer drop. They can be bought on the AH still but are way to expensive for it to be worth it. The Excess Potion of Accelerated learning is available from your garrison quartermaster but only works for level 91 to 99. As of Patch 8.1 you can also buy the 10% XP Potion Draught of Ten Lands.

Island Expeditions:[5] 3-Player co-op with optional 3v3 gameplay. Players will explore uncharted isles across the Great Sea. There is azerite and other unclaimed resources bubbling to the surface that is highly sought by both factions. Complete varied and dynamic objectives with a large variety of challenges to overcome. Race against advanced AI opponents designed to thwart players using tactical and strategic moves that consistently change. Optionally, players can choose to race against other players, creating a 3v3 PvP environment. 
It can be quite difficult to begin the new WoW expansion. There's a long, even huge adventure ahead of you, 10 levels to reach (up to 120 levels) and hundreds of new quests. The question about how to get to Silithus is actually how to start the expansion of Battle for Azeroth. We present few ways to get to Silithus from both sides - The Horde and The Alliance. You will learn how to get the Hearth of Azeroth necklace and what conditions you have to meet in order to unlock your quest.

Each of those modes existed long before this latest expansion; raiding is a basic concept in MMOs, and Mythic+ was added in World of Warcraft’s last expansion. The problems with Battle for Azeroth’s endgame come from the systems it adds, which most often artificially gate progress where most of the fun can be found. If raids and Mythic+ are the carrot, we’re about to talk about the stick.

The raid is made up of eight bosses that each have interesting and unique mechanics. Some bosses might put extra pressure on the DPS players to kill an add before it can heal the boss, while others might require players to move around the environment in a specific pattern or order, all the while still doing as much damage to the boss as possible or keeping the group alive through healing. While past raids often repeated mechanics or had one or two boring fights that didn’t ask much of the players, each encounter in Uldir feels unique and challenging. It’s been a long time since we had a raid where each fight was as much fun to do over and over again as the fights in Uldir.

There’s a lot of #content in the new expansion. It’s mostly locked behind a variety of gates, some of which players can’t even control. Warfronts are the best example. You might assume joining a Warfront is a simple matter of opening the group finder. Wrong! Warfronts are only accessible for a week at a time. It’s not precisely clear how often that week will come around (it’s based both on a time gate and on the opposing faction gathering resources) but, as of right now, it looks likely to be available just one week out of every four.
For reference, my previous best time abusing Method-0 in 7.3.5 was 32.4 hours(as show in the old thread). A difference of just over 8 hours; which isn't all that bad, all things considered. And I believe I made several errors along the way, which could be cleaned up in future runs. I believe that that gap could be significantly closed by using a monk's bonus, but I hate playing monk...so...yeah. YMMV