This Shadow Talent Build is the fastest for Leveling Up a Priest Class from 1-60 in WoW Classic patch 1.12. Spamming Shadow Damage DOTs while kite mobs will be the name of the game with this build, having the ability to sustain your health is just a bonus. You will just need to make sure you are stacking enough spirit so you don’t run out of mana often as that will slow down the levelling process drastically.

Thanks for bringing this question to our attention. Addons and their availability are a large part of what makes WoW great. Any addon that enhances your User Interface [UI] is totally okay, however, anything that automates your character's play [you can walk away from your computer and your character is still leveling, in combat, etc] is decidedly not okay and falls under exploitation and botting. If you are concerned at all or think the particular addon/guide may fall under that second category, for your safety, I recommend you just stay away from that one as violations of the Botting/Exploitation aspect of the Terms of Use is a bannable offense. If you have any questions about what might be considered automated play, I recommend you refer to the Terms of Use and follow them to the letter. You may find those Terms here: http://us.blizzard.com/en-us/company/legal/wow_tou.html.
One player said in a comment posted in response to the list, “Yeah people don’t realize the sheer enormity of game system evolution WoW has gone through since release. I’m not the biggest fan of BoA by any stretch, but I’ve played since closed beta vanilla, and I doubt I’ll be going back to classic. Leveling was painful. Experiencing these old systems once was enough.”
Zygor's Leveling Guide for The Elder Scrolls Online (PC Version) is an in-game, software based, strategy guide that will show you the quickest way to level your characters from 1-50. You can view and use the guide directly inside the game without having to print out anything or view the guide in a browser. This also means that our guides are dynamic and can track your progress in realtime.

Within the context of Classic, the method most frequently proposed is to re-tune bosses to make them harder. Rather than copying the numbers, re-create the relative difficulty. Kind of like, when you first start working out, you use small weights. When you get stronger, you lift bigger weights. The WoW community is more knowledgeable, more experienced, has better hardware, etc. We're "stronger." So give us tougher bosses. There are a lot of forms that could take. Bosses were constantly re-tuned during vanilla anyway, so if Ragnaros does 10% more damage or something, is that really a problem? I don't think it is. What about resistance gear? back in the day, collecting resist gear was a thing people did. But the numbers and strategies are so well known today that only the tank really needs it anymore. Bosses could be re-tuned with more resistible elemental damage so that's important for entire raids to gear appropriately. That would be entirely keeping with the spirit of vanilla even if the actually numbers sitting in a database somewhere were different than they were ~13 years ago. If you want to go a little farther, a few people have proposed adding new abilities to old bosses, adjusting their timing, etc.
I think you are referring to the Env Bert strat I have linked. Basically I agree. But you might have noticed that I already had added min power to pet #2, in order to exclude some of the substitutes. Though, I didn’t wan’t to do the same with the Blazehaound (pet #1), because I think the strat is doable also with a suboptimal breed. But maybe you are right and I should just exclude any non-P/P breeds.
It's time to do this again!  I am bringing this back for nostalgic value along with a way for you guys to support me!  Now keep in mind I am sending the very first original version of my leveling guide for Horde (I did not make an Alliance guide back then).  This is not really meant to be used to level through WoW, even though you could use it for that purpose.  My website JoanasWorld.com contains the latest up-to-date version of my leveling guides which have changed a lot over the years.
Other methods have been discussed. For example, mods could be crippled. DBM didn't exist back then, and the other boss that did that I don't remember the name of, didn't do as much back then as DBM does now. If our goal is to recreate the experience as it was, then obviously not having DBM would be a reasonable way to accomplish that. DBM simply existing, makes the game today easier than it was. So disallow it. Again, this is completely consistent with the spirit of vanilla. Remember one-button-decursing? That was nerfed. They crippled the capabilities of the modding API to disallow that because it made the game too easy. So what if they cripple it a little bit more to once again make the game less easy?
Much like an encounter with a wild pet team, PVP Pet Battles are turn-based. However, unlike the PVE version, the PVP combat system is timed and any ability for each round must be chosen within that time limit otherwise it will assume you have passed a turn. A time penalty is applied if you take more than 15 seconds to choose an action, resulting in progressively shorter round timers for you.
Swim Speed Potions (used especially at lvl 37 for Faldir's Cove in Arathi Highlands and lvl 57 in WPL).  Try to get multiple stacks of these.  I also recommend keeping a stack of these always in your bags.  You will frequently pass rivers and lakes and can use these potions to pass them faster through out the guide.  Please note that these potions do not stack with Druid's Aquatic Form and Glyph of Aquatic Form.
On March 23, 2018, Zygor Guides announced that they would end support for their ESO guide. Later, via answers given on the forums, they confirmed they would not add a leveling guide for Summerset. Their guide is Public Domain with Zygor's blessing for the community to create guides. So I took it upon myself to create a Summerset guide for the ESO community.
Zygor's Leveling Guide for The Elder Scrolls Online (PC Version) is an in-game, software based, strategy guide that will show you the quickest way to level your characters from 1-50. You can view and use the guide directly inside the game without having to print out anything or view the guide in a browser. This also means that our guides are dynamic and can track your progress in realtime.
Some players have been surprised by these apparent flaws—even players who have been eagerly awaiting WoW Classic's release based on fond memories of vanilla WoW. In truth, it has been so long since WoW first released, players' memories may not always be accurate. Some details might be fresh, but others might be lost in time, and it's those lost details that could surprise players revisiting the original experience in WoW Classic.
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