There's a new Merchant system in wow forever that offers very powerful new crafting recipes for every profession. These recipes all require a new currency called merchant's favor to purchase which you get from filling and turning in
Waylaid Crate: Apprentice Herbs and various other Waylaid supply crates. You can buy crates or find them on your own and there's lots of different kinds.
If you're wondering where you can find these merchant hubs The Alliance one is located southwest of Redridge on the boarder of Elwynn and Duskwood an area called the three corners. And for horde you can find it just west of crossroads in the barrens. Both locations should be relatively easy to get to on fresh characters looking to get started on their professions.
Higher level recipes will require reputation. You get a one time 2000 Reputation boost from filling your first
Waylaid Crate: Apprentice Ore or any other kind of crate. And then turning in the "Shipping Label" Quest item that you get.
The Reputation needed is the Azeroth Commerce Authority for Alliance and the Durotar Supply and logistics for horde. The higher level Recipes will require higher rep in addition to increasing amounts of merchants favor.
Craftsman's Writ: Azure Silk Hood ,
Craftsman's Writ: Ornate Spyglass, and other various Writs can be turned in all over the world along with the crafted item for 75, 125, or 200 reputation depending on the level of the craft & Writ.
Both Crates and Writs can be found in normal adventures, with a higher chance from chests. Or they can be purchased on the Auction House.
Profession recipes aren't the only rewards you can get though with this new faction. They also offer a Pack Kodo epic mount for 6000 merchant favor and exalted with your respective faction. There's also a few other non-combat items you can get as well. This adventuring license quest item gives you a quest to get a profession signpost toy item. There's also a companion pet, and a tabard all requiring various amounts of merchants favor and reputation levels too.
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If you want to get a look at the vendors and view what they sell and see some crates and writ turn ins, I have a full accompanying video guide posted on the right with full commentary.