Primary Professions-
This is primarily about the simple outright benefits of the profession that affect your character directly and not so much the combination of professions to benefit each other.
Alchemy-
Benefit- Mixology- You receive increased effect and duration when you drink any flask or elixir you are able to create. 37 spell power and double duration on flasks and elixirs.
Instead of receiving 125 spell power from Flask of the Frost Wyrm, you will receive 162 and it will last two hours instead of one. Alchemy also allows you to make various elixirs and potions that can be useful in many situations around Azeroth.
Blacksmith-
Benefit- The ability to socket bracers and gloves. 2x 19 spell power gems = 38 spell power increase.
Blacksmithing is by far the most expensive profession to level up these days and since the only thing you gain is the sockets and none of the gear you can create is wearable on a Warlock this isn’t the best choice for you.
Enchanting-
Benefit- 38 spell power
Enchanting offers you ring enchants. The best ring enchant for Warlocks is +19 spell power. Therefore with 2 ring enchants, Enchanting offers you 38 spell power. Enchanting is also a great money making profession. You will be able to disenchant all the gear you would normal vender away which ends up making you a ridiculous amount of gold or an abundant amount of shards/dust in your bank.
Engineering-
Benefit- Jumper Cables, Repair Bots, decent headgear, and trinkets.
Engineering isn’t a profession that’s going to directly benefit your DPS. With endless trinkets and doodads, Engineering is an extremely handy profession though.
Herbalism-
Benefit- Life Blood: Uses your skill in Herbalism to absorb energy and nutrients from the earth, healing you for 2000 over 5 seconds. (level 80)
Combined with Alchemy or Inscription Herbalism becomes even more valuable. I don’t see Life Blood as an ability to make your decision over. Herbalism’s real benefit is the ability to save gold by allowing you to pick herbs instead of having to purchase them from other players.
Inscription-
Benefit- 37 spell power.
Inscription workers have the ability to create and wear the best shoulder enchants in Azeroth. If you are exalted with Sons of Hodir after weeks of daily quests you can get the 24 spell power, 15 critical strike enchant. With Inscription, you have an enchant that offers 61 spell power and 15 critical strike available to you. Other than that, inscription requires herbs and is fairly easy to level. Be careful at higher levels though, the best patterns come from rare books, so, make sure you have the ones that take the least amount to create before you start wasting materials.
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