Priest is a caster class who is between healing power of Light and burning mind power of Shadow. Though they use only cloth armor, their spells and skills provide a high survival rate in combat: non-stop healing, absorbing shields and restoration. Priests are the best for those who loves to heal and save others lives.
Their main feature is multifunctionality as a healer. Great number of healing spells, they are always welcome in any raid and dungeon group. Extra beneficial skills at their disposal: cure diseases and dispel magic effects, powerful stamina buff, resurrection, mind control, mana burn, levitation (allows to walk on the water) and not only. Discipline and Holy talents are focused on healing, Shadow specialization is based on constant damage.
Leveling
The priest leveling is not that easy and not more difficult as others. Unlike warlocks, priests have to make short mana regenerating pause. They don’t have strong AOE spells, that means only one opponent per time is preferred. No extra speed movement abilities make you rather slow till level 40.
Good to level and PVP in Shadow spec and join dungeons as a healer or DPS caster.
PVE
In PVE priests focus on healing mostly. If you are only Shadow oriented, you will always get a spot in a raid too, “Shadow Weaving” ability increasing shadow damage for all group members.
To optimize and regulate mana rate they use different ranks of same spells.
PVP
In PvP priests are less effective as healers, than in PvE. They lose to paladins in survival and to shamans in universality. Shadow Form combines with casting DOTs, enemy control and absorbing shields.
Race
Racial choice for priest is more complicated, than for others. Each race gets two unique spells. There are Humans, Dwarves, Night Elves, Undeads and Trolls available.
Human-priests get 5% bonus to spirit, that combines with talent in Holy tree “Spiritual Guidance” and increases damage and healing from your spells and provides fast mana generation.
The unique spell of Humans is “Feedback” (useful in PvP, it burns enemy’s mana and causes damage) and “Desperate Prayer” (heals the caster, good for both PVP and PVE).
Dwarves have racial “Stone Form” (increases armor and gives immune to diseases, poisons and bleeding effects). As priests they have “Fear Ward” (gives immune to Fear effects to a friendly target) and “Desperate Prayer” (heals the caster). Stone form makes them more resistant for PvP and “Fear Ward” is significantly essential for different bosses in raids, making dwarves popular for PVE as well.
Night elves has racial skill “Shadowmeld” (allows you to stay invisible while you don’t move). It’s good for PvP. Their “Stashards” causes arcane damage with low mana cost and cooldown.time. “Elune’s Grace” decreases any melee and range damage hit chance by 20% for 15 seconds.
Trolls is more relevant race for PvE due to their “Berserking” ability, increasing casting speed. The unique trolls spell is “Hex of Weakness” (decreases targets damage and healing) and “Shadowguard” (gives caster temporary effect, damaging attackers).
Undeads have racial “Will of the Forsaken” ability that removes Charm, Fear and any Immobilizing effects. The unique class spell is “Touch of Weakness” (decreases enemy’s damage) and “Devouring Plague” (causes Shadow damage and heals the caster).
Professions
With Tailoring you can craft and use Truefaith Vestments, BoP (binds on pickup) Epic robe for priests use only. It can be equipped even if you unlearn Tailoring, but Bloodvine Set becomes unavailable then.
Skinning or Enchanting is usually taken as a second profession, so you can always supply yourself with leather of all kinds or disenchant green quality crafted items.
Engineering is required for all PVPers, as it gives great advantage and increases your survival rate. Usually it does not cost lots of gold to buy reagents on Auction House if you do not pick Mining in pair and prefer anything else.
Herbalism and Alchemy are always good to make money and have your own flasks, potions, and elixirs for PVP and PVE.