Why was this downvoted? The swing analogy is horrible. There’s nothing physical that’s going to change when u play the game the exact same way as 04 05 06. The difference is u know what’s going on as opposed to not knowing where anything is. A good analogy would be playing Pokémon red again after beating the elite 4. The game itself won’t be any worse, it just will be easier and maybe less enjoyable if all you enjoyed is the aspect of not knowing where to go. But this is why pvp servers are magical, because each time you level a character, your leveling experience is different based on the encounters that happen while questing. In 05 U may have breezed through stv, but in classic u may spend an hour on a single quest solely because of the competition between factions on that particular quest. 

WoW Classic seeks to recreate the "vanilla WoW" experience—that is, WoW as it existed before a series of seven game-altering major expansion packs from 2007's The Burning Crusade to 2018's Battle for Azeroth. To achieve this, Blizzard has rebuilt the game based on archived data from back in 2005 and 2006 (patch 1.12 is the goalpost—the current game is on patch 8.1.5). The company has committed to meticulously presenting the experience exactly as it was back then—warts and all—with only a small number of unavoidable or critical changes.
When it comes to levelling the Priest Class from 1-60 fast, XP grinding locations is only half the battle. You will need to make sure your weapon does enough DPS so that you can clear these mobs fast enough, it should also be noted that monster should be around your level to make sure to gain the 100% XP Reward. The Level your character should be before you start that specific location will be indicated to left in a Blue Color for Alliance [Lvl 35-39] and the Orange Color for Horde [Lvl 35-39]. The Mobs you are looking for in that specific area names are Bolded [Mob Name].
All of this is keeping with the spirit of vanilla, which I think is more important than that a specific number be 11 instead of 12. And it would help to "resize the swing" by making the game harder to the more experienced community, and forcing people to re-discover the game rather than simply looking up whatever they want to know on a spreadsheet somewhere.
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.
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