Traders or Merchants are in charge of sailing around the world finding the best and most exotic goods to trade in. Buy low and sell high is their motto.
They are also responsible for crafting various goods from Cooking to Alchemy!
Basically job define a set of skills. When you apply a job, you can obtain the skills related to that job easily.
You need a Certificate / Permit to apply for certain job's. You obtain the Certificate/Permit by finishing a certain Quest. You can change your job any time you like.
You can reapply for a job that you have already completed, any time you like, and for that You don't need a Certificate / Permit any more. To change your job, you just need to visit a merchant Guild Master (GM) at Merchant Guild in any big city.
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