Second: I have found that the most effective way to level (which comes as no surprise to many) has been using the leggos KJBW and Sephuz’s. KJBW allows you to complete nuke down packs of mobs no problem on a 75 second cd and since the damage doesn’t fall off you can clear 10+ mobs in seconds.Edit KJBW has been nerfed to do half the damage that it normally did. It is now a 3.2k Nuke on 75 second cd that doesn't fall off. Though it is sightly more balanced, that does make me sad. I still believe that it is probably the best leggo still to level with but I will do some more research to confirm. Sephuz’s is nice for the MS boost and the proc is no joke. I highly recommend these for every class.
To put that in perspective, the high-priced vanity mount released with Legion is a giant spider called the Bloodfang Widow. It costs 2 million gold. If you wanted to buy one with cash, using WoW tokens, it would have cost over $1,100 at the time Legion was released, in August 2016. If you wanted to do the same thing in July 2018, it would have cost less than $200.
A much smaller number of players are producing surplus quantities of those valuable goods and providing them to other players. And all the gold generated by the activities of those players who ignore the grindy professions and get what they need from the auction house is flowing to the players who are making all those goods available on demand to the rest of the community. Most of these auction house merchants are sitting on a lot of gold, but the number of people who want to make cash this way is relatively low.
 ":"  -  Any time a step ends in a ":" instead of a "." means that the next step is part of the current step you are on.  This generally means the next step should be done while working on the current step.  This means every "start working on" or "continue working on" will end in a ":".  But this is used with other occasions as well, so keep this in mind. 

First off, there is no reason to ignore the war Campaign, you need to do them to unlock world quest. Beside that, the way scaling works, war campaigns are easyer to do while leveling then at 120. Everything becomes alittel harder at 120, untill you get some gear, because of them scaling levels. Also, i did my leveling on a demon hunter in about 8-9 hours. I think i know what youtube video you talked about, and i strongly dissagree with him. One thing tho, total xp needed was buffed with 15% that in worse case would make me take 10hours, the way i did it.
I used fully upgraded and enchanted heirlooms; missing only the fishing ring. Leveling from 1-20 took ~3 hours, at which point I immediately turned on War Mode for the duration. I rarely encountered enemy players, and when I did they almost always left me alone. But the few times I did get ganked, the total cost in time was insignificant. Maybe a total of 5 deaths from ganks in the entire 40 hours.
Footholds into enemy territories can be done as you grow in levels and should be completed before reaching Level 120. Take the time after completing your first zone to do your first foothold. Similar to how your initial zone selection was largely irrelevant, this selection is, as well. Simply pick one and complete it to earn your Mission Table second champion. Send your champions out on missions, recruit troops, and then head back out to quest in your second zone selection.

Full disclosure on my time with Battle for Azeroth thus far: I leveled a Horde character to 120 and completed all three Zandalar storylines plus put about 20 hours into end-game content. I have also leveled an Alliance character partway through Kul Tiras and completed portions of the Stormsong Valley and Tiragarde Sound storylines. My only experience in Drustavar has been through the eyes of the Horde thus far.
Fish, meanwhile, were significantly devalued by the Underlight Angler, an artifact-quality Legion fishing pole that made fishing so productive that a very small number of fishermen could supply an entire server with materials for cooking. At current rates, fishing in Battle for Azeroth is more time-consuming, which means less food to go around, and higher prices at the auction house. Of course, Blizzard could change spawn rates in a future patch, but as of now, signs point to an economy in which common necessities will be much more scarce.

I had multiple people ask me why I didn’t do blood or prot for leveling on DK/Pally and the god honest truth is the fact that I know how to play ret and unholy quite well and the limits of the class. I tried leveling as prot and good Christ it felt like I did no damage. If you take selfless healer and wake of ashes you should have 0 issues with leveling as Ret and it is significantly faster. As for Unholy if you take grip of the dead to kite a little, deathpact for healing, and keep up with your Dark Succor (spelling?) procs you will have no issues. I died once as DK and none as pally. The only classes I struggled with a little was WW and Shaman. WW because the aoe felt under-tuned at the time and shaman because they are trash imho.
Congratulations on reaching Level 120! There are a myriad of new things to do. The first thing you should do is head to your faction hub ship where you have been doing your mission table quests and footholds to pick up and complete the quests necessary to unlock World Quests. World Quests will provide you an opportunity to grind reputation levels, acquire gear, and gather Azerite. There are tons of new things to do that we will cover in our Level 120 Battle Guide found here: Level 120 Battle Guide
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