It is true that every spell has some use. There is at least one scenario where every priest spell in the game is worth using. However, while leveling, some spells are simply unnecessary, and learning them is nothing more than a waste of money. Other spells (like Smite) are useful very early on, but quickly become useless as other spells become available.

Sulfuras, Hand of Ragnaros is possibly the most famous item in all of WoW. One of only two legendary items introduced with the base game, its power may not have lived up to its legend, but the effort you had to put in to get it most certainly did. Today we'll be taking a look at the weapon and how good it was in patch 1.12, how to get it, and we'll throw in an extra story related to it from Vanilla.
Elune’s Grace: On-use ability that reduces damage taken and increases dodge chance by 10% for 15 seconds. 5 minute cooldown. Useful if there are a lot of mobs attacking at once, or if fighting mobs that attack often, such as dual wielders. Also useful in PvP in similar situations, such as against rogues or feral druids. Less useful against slow, hard hitting mobs or players.
Since the beginning of beta, we’ve seen a lot of bug reports around the Hunter class in particular, and we’ve been working diligently over the past weeks to shore up some of the issues that players have been reporting to us. We felt that it would be helpful to post an update on our progress as well as to clear up some confusion around issues that were reported that are behaving consistently with the Reference client and are not considered to be actual bugs.
Agility increases one’s armor, dodge chance, ranged attack power, and ability to crit with all weapons. I have been unable to confirm or deny whether this affects wands (everyone instantly calls you an idiot or a troll if you ask these kinds of questions). It is probably safe to assume that, as intended, priests do not want to prioritize Agility. However, it isn’t a totally useless stat, as armor and dodge chance are beneficial for leveling.
 ":"  -  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.
While consumables certainly aren’t everything, they definitely make a big impact. Without consumables, shadow priests probably would never be invited to raids considering that they’d always be out of mana! If you do your best to stock as many of these consumables as possible, you should never run into mana issues. You’ll also notice that they help your spells pack quite the punch, what’s not to love other than the time and cost to acquire them?
The weapon is usable by Druids, Paladins, Shamans and Warriors, and while it's probably the best weapon for Enhancement Shamans and Retribution Paladins, those specs weren't really popular or very viable back in the day, so Warriors were the primary wielders. Before going into the arduous journey you needed to go on to acquire this, we need to mention Sulfuras definitely was one of the most powerful weapons throughout all of Vanilla, but there have been many discussions about whether it was ever really the very best for any class. 

Touch of Weakness: On-use ability the applies a buff to the priest, reducing the damage of the next melee attacker for 2 minutes. Lasts 10 minutes. Decent for leveling when fighting mobs that hit very rapidly, such as dual wielders, or in PvP against similar targets, such as rogues or feral druids. Less useful against slower, hard hitting mobs or players.
Nihilum wasn't a big guild yet, it was still pre-Blackwing Lair times and we were farming Molten Core. For some reason we had a massive number of Warriors in the guild, including Kungen, the GM, with around 8 being in pretty much every MC raid. As you'd imagine, every one of them wanted that shiny fiery hammer for themselves as you couldn't really have 8 tanks in the raid, so most of us were DPS/offtanks. The guild ran on a standard DKP system and most players had a solid amount of gear from the raid already, so every DPS Warrior was gathering their points for that Eye drop. I was the first in line for the Eye so it was a simple matter of saving up my DKP and having the Eye actually drop.

Hunter “dead zone” is working as expected and is consistent with the Reference Client A wolf pet’s Howl buff is consumed by anything that causes damage, even if it does not benefit from the buff A Hunter pet’s Bite and Claw ability damage will not change in the tooltip based on the happiness of the pet. The tooltip will always display the damage as if the pet were Content (yellow). This is consistent with the Reference client Note: This was reported several times to us based on 1.2 patch notes which seem to have been misunderstood. The intent here is simply that damage displayed is what the pet would deal if it were Content, not what it deals based on its current happiness level. Traps can sometimes not be triggered if a player moves over them very quickly (i.e. a Warrior’s Charge ability). This behavior is consistent with the Reference client. Auto Shot does not make a sound when cast during the animation of Hunter’s Mark and certain other abilities Scatter Shot and Freezing Trap share diminishing returns The following reported issues are either confirmed fixed in recent builds, or we have upcoming fixes currently in testing:
Picking the best race for the priest is difficult since this class gets unique spells based on its race, these affect how we rank the best drastically. For Horde for sure if you are going shadow you will want Undead, and Alliance can choose between Humans and Dwarves. With PVP in mind, we think Dwarves have an edge of humans, but they are both good choices so either will work.
Don’t ever worry about the armor value or level of gear. The other stats are what are important. The amount of damage reduction gained by focusing on armor values will make little to no impact on leveling at all, and never look at the gear equipped on a character and think it needs to be replaced because it’s “outleveled.” The level of the gear is irrelevant. Vanilla has some terrible items. Level 40 gear can have worse stats than a level 20 item with great stats. Great pieces to look out for are the Dreamweave pieces, the Shadoweave set, Honored PvP reputation gear, and any decent cloth boots, because for whatever reason, good cloth boots are hard to come by.
1 Eye of Sulfuras And there you have it. Obviously Sulfuras is very much a guild-wide effort and the most common path to getting it is to have the guild gather up all the mats collectively, to then give to whoever earns the Eye - either through DKP or whichever method the guild uses. However, since pugs will be much more of a thing in Classic than they were in Vanilla, it's not completely insane to think someone will want to do this solo/without guild support, but for that you'd either have to have a whole lot of gold (not to mention luck to even get the Eye in a pug) and perhaps do some planning ahead of time, especially with the transmutes.
Fear Ward: One-use ability that grants a friendly target immunity to the next fear effect used against them. Can be dispelled. Lasts 10 minutes. 30 second cooldown. Incredible in PvP. Great for a raids, but not very useful while leveling or in 5-man dungeons. However, because of the short cooldown, there’s no reason not to keep this buff up in case anything (or anyone) has a fear.
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.
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.