If you want to spend as little time on your alt as possible - just do Legion Invasions. You can use sites like (https://wow.gameinfo.io/invasions) to track when the next invasion will be. Log in, fly to the closest world quest, and once there - right-click on the quest's name in your quest log and "Find Group". Sign up for some group, or if there's none - just start your own immediately, and people will come to you. It is 10 times faster to do invasion quests in a group. Once that particular quest is complete - leave the group, and fly to the next one, where you should find another group. Don't expect the group from one world quest to follow you to the next. Then you simply log out until next invasion. You can do 1-2 invasions a day, and each invasion will give you about a level or 1.5 of experience, if you have full heirloom gear. Each invasion will take about 20 minutes.
Tiragarde Sound and Stormsong Valley are both fairly similar zones, but Stormsong is a little longer, meaning that you might not even have to finish it to hit 120. Tiragarde also comes with a bit of a warning. There are plenty of side quests to do in the zone after you finish the story quests. Don’t do them. It’s not worth the time or the experience you’ll get.

This is also the reason why when I read in WoW forums of people skipping guide sections, due to being too low level I'm not agree and start ranting about it: it'll be a mess syncronizing with the guide and I've seen many people complaining about missing quests or accusing the guide for being innacurate, but not realizing that was their fault since they're skipping and missing a lot of quest chain requirement. Of course this apply if you're following a guide, believe me, it's very frustrating when you remain stuck in a guide section due to the reasons I've mentioned, more than doing grey quests (but they allow to be perfectly in sync with the guide) and goiing here and there to get the pre-requisite quests.
At 98 you have the option to drop what you're doing and return to your capitol city to start the quest for your Legion Artifact weapon. However, I do not believe this is necessary to do right away unless you're struggling with kill speed in your current gear. I would recommend waiting for a natural pause, such as hearthing to repair and clear your bags. From 100 to 107 you won't even really fight mobs that often; only just enough to clear the way to any treasure you need to pick up.
Incursions are a new world content activity that are unlocked when one character has unlocked World Quests. This feature is unlocked account-wide meaning that all characters on that account can access Incursions even without being Level 120. This provides for a lucrative experience acquisition method that is available in a similar pattern to what Legion Invasions offered with nearly an entire level earned by completing an Incursion series which involves four World Quests and one mini-scenario at the end. These also grant item level 370 weapons and Azerite armor, so they should be done any time they are up. Incursions follow a similar schedule to Invasions and are available for 20 hours once they are initiated.
Elixirs serve the same purpose as Flasks, but the buff expires if you die. You'll only use these between 1-70, generally speaking, until you can start buying Flasks which persist through death. Try not to die, and carry extras just in case. If you can't find an Elixir with the stat you want, look under scrolls, since they count as battle or guardian buffs as well.

Island expeditions - Set sail for the previously unmapped isles of Azeroth. Battle in groups of three as you race against cunning rival intruders—or enemy players—to collect the island's resources. Constantly evolving challenges await as you traverse frozen landscapes near Northrend, open the gates of an abandoned Gilnean castle, navigate a war between elementals and more. Can be done either in PvP or PvE against advanced AIs.

Despite the fact that World of Warcraft still relies on the old 14-year-old game engine, the game can cause some frame rate drops even on newer hardware equipment. So we've decided to devote a lot of time and space to answer such questions like: How to set up the graphical options? What should I do to make sure that WoW runs smoothly? WoW's hardware requirements have evolved over the years due to graphical improvements, so find out if your computer can handle the highest graphics settings of the game.
Even if you don’t have flying in WoD be sure to get the WoD handy notes. If you have flying simply fly and pick up all the treasures that you can and do bonus objectives. Not every single piece of treasure will be worth it though as some are hidden in caves or are just hard to get. So if you find yourself spending more than a few minutes finding a treasure, just skip it and move on, there is plenty of treasure to go around.
Once you reach an Alchemy skill of 475, you may begin a quest to learn one of three specializations: Potions,Elixirs or Transmutations. Being specialized gives you a chance to create an extra 1 to 4 (for a total 5) items while crafting in the field you have selected. For example, a Master of Potions may be able to craft more than one [Super Mana Potion] for the same material cost as one.

As late as possible. Early on, you’ll want to follow the missions in Battle for Azeroth right up until you get the option to send a follower on a two-hour long quest. As soon as you get there, stop doing the War Campaign missions. You can come back to them once you have reached something like 119 and a half and finish leveling with those if you want. If you don’t use these missions to cap off your leveling journey, then they’re the first thing you’ll want to do once you reach max level.
Meanwhile, Tyrande Whisperwind and Malfurion Stormrage grow impatient regarding liberating Darkshore from the Horde's control, ultimately choosing to begin the offensive on their own, against Anduin's advice. In order to maximize their chances, Tyrande undergoes a ritual to turn herself into the Night Warrior, the avatar of Elune's most wrathful and warlike aspects. To counter this, Sylvanas orders several Night Elven heroes who fell in the Burning of Teldrassil to be raised as Dark Rangers to bolster her forces.
As always, I will monitor and update this guide as new information comes in. If I've gotten anything glaringly and completely wrong, just tell me with as much data as possible. The idea is to find the fastest possible leveling method, NOT to argue about how good or bad individuals are. If you have hard data, post it! If you have an idea, let the thread know so we can test it!
I am currently working full time on my Vanilla WoW leveling guides.  Soon there will be a 1-60 speed leveling guide for Alliance, along with in-game guide versions available for my members area.  As of right now, there is no members area, but if you would like to show support for my efforts into this project, you can simply donate to me via Patreon if you like (you will get some cool rewards in return).  Or you can donate directly with PayPal if you like.  All donations are highly appreciated and they will only motivate me more to continue making the best vanilla WoW leveling guides on the web.
-Azerite Gear- This has been the worst experience for many players as it was advertised as offering the player many options for customizing their character but all players do is Google "Icy veins (Spec/Class) azerite ranks" and select the best one. This is expected and really only gives players the illusion of choice as they're always going to pick the best one. This could have been done far better by not offering necessarily just damage increases in traits but offering some of the Legion Legendary item effects in Azerite slots. You know, certain Azerite traits would be better for PvP, some for raiding, some for 5 mans, some for soloing old content, etc. The other problem with Azerite gear is that it's locked based on you grinding an endless amount of Azerite for your neck piece (basically the stuff that increases the level of your neck piece). So when you get an item that should be an upgrade, it really isn't because you don't have all the traits unlocked. This complaint about how horrible this system is could go on forever, but I'll just leave it at that, horrible.
Dugi and Zygor both had their guides updated before Mist of Pandaria was released and both guides are kept updated with all the patches and changes to the game. Dugi is way faster with updates and has a lot more. Zygor seems to hold out and then do a big update. With new content such as guides etc, Dugi is definitely leading the way with Zygor usually many months behind. Zygor now offers the same number of guides as Dugi but it took them a long time to catch up.
 Nightborne - "Isolated behind a protective barrier for 10,000 years, the elves of Suramar grew increasingly dependent upon the arcane magic of the Nightwell. To protect this font of power, the leaders of the Nightborne struck a bargain with the Burning Legion that plunged their kingdom into civil war. After fighting for freedom from their demonic masters, the Nightborne seek allies in the Horde to help them reclaim their place in the world."

That’s because armor of higher level has higher Azerite power requirements than lower level armor. That means a shiny new piece of Epic gear will have better stats but, unless you’ve been diligent about your Azerite power grind, won’t have as many traits unlocked. You lose options as you earn better gear. Eventually, you’ll grind out enough Azerite to earn those traits back, but you’re left with limited customization until then.
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