Translated automatically from Italian: talent and ability names stay in English, as in the game. Original text (Italian) →
This build takes the Priest to 60 with Shadow spells and the wand, and thanks to Spirit Tap you rarely stop to drink. Shadow Word: Pain, Mind Blast and Mind Flay do most of the work, the wand ends the fight, and from 42 Shadowform halves the cost of Shadow spells.
How to play it
With this build every enemy follows the same script: you wear it down with a couple of spells, finish it with the wand and move on with the mana Spirit Tap gives back to you. Once you have the rhythm, downtime is almost zero; mana stays tight only until Shadowform. On gear, look for spell power first, then crit and a bit of hit (little against enemies of your level, more for dungeons and elites), then Intellect, Spirit, Stamina and mana per 5 seconds.
From 10 to 60, step by step
10–11: Wand Specialization: early on, a good part of your damage comes from the wand.
12–16: Spirit Tap, the key talent for leveling. A kill doubles your Spirit and lets half of your mana regeneration continue even while casting.
17–25: Improved Shadow Word: Pain (lasts longer) and Improved Mind Blast (shorter cooldown), with Mind Flay at 22 and Improved Mind Flay at 23–24. Mind Flay replaces Smite as your filler and each tick hits harder than the last.
26–27: Shadow Reach and Vampiric Embrace, which heals you with your Shadow damage; enemies that die with the effect on them trigger Spirit Tap, which is very useful in a group.
28–34: Dark Inspiration, which gives Spirit to you and your party after Mind Blast and every full Mind Flay, and Devouring Contagion: Devouring Plague costs half and, if the target dies, jumps to two nearby enemies.
35–42: Silence, one point in Shadow Weaving, Darkness and, at 42, Shadowform, which halves the cost of Shadow spells. Darkness, Shadow Weaving and Shadowform are the core of your damage.
43–53: Twin Disciplines and Mental Strength in Discipline to reach Meditation (half of your regeneration even while casting), which only comes near the end.
54–56: three points in Twilight Focus, in the Holy tree: you lose less casting time when you're hit.
57–60: the last two points in Shadow Weaving and two in Shadow Focus, for better hit in dungeons.
The rhythm of every fight
Before attacking: Power Word: Fortitude and Inner Fire. If the enemy will reach you, put Power Word: Shield on yourself: it prevents cast delays and protects the 20 charges of Inner Fire, which in Forever are used up by the attacks you take. In a group or against enemies that stay away, you can do without it.
Open with Mind Blast (with Smite until you have Mind Flay), then Shadow Word: Pain. Devouring Plague and Mind Flay only if your mana allows it: below 30 you usually skip them, with Devouring Contagion and Shadowform they become worth it.
Finish with the wand: the 5-second rule ends sooner and Spirit Tap procs in full when the enemy dies. The secret is casting just enough for the final blow to come from the wand. Shadow Word: Death is for a final burst, but if the target survives it costs you health.
When things go wrong
Renew your shield if Weakened Soul allows it, then Flash Heal, Heal or Lesser Heal. Psychic Scream only as a last resort: fleeing enemies pull others. You have no real AoE damage: you can spread Shadow Word: Pain over a few enemies and take them down one at a time, but only where you know you can handle it.
Strengths
Almost no downtime once you get the rhythm.
Heals itself and has sturdy shields.
Lots of utility and buffs for the group, from Power Word: Fortitude to Vampiric Embrace and Dark Inspiration.
From 42, Shadowform halves the cost of Shadow spells.
Weaknesses
Tight mana until Shadowform.
No real AoE damage.
Little mobility.
It's made for leveling: at 60, for dungeons and raids, it's better to change talents.
Notes
Change wands often: in the early levels the wand does about 40–50% of your damage.
Power Word: Shield is your best leveling tool: it absorbs damage, prevents cast delays and protects your Inner Fire charges.
In Forever the Priest gets two exclusive racial traits through class quests, the first at 10, on top of the usual ones.
Shadow Word: Death is already available while leveling.
Dungeon quests give a lot of experience: complete every zone, because its quest chains often end in the nearby dungeon.
Log out in an inn or a city, so you build up rested experience faster.
Professions: Tailoring to dress yourself while leveling, Alchemy for potions and elixirs.
Race: Human, its Spirit bonus goes well with Spirit Tap.
