Tetrarch Thifiell:
In order to become an Assassin, you must have achieved at least level 20 and passed the test of the Assassin.
Even after meeting these requirements, you'll not be allowed to transfer class if you just stay here. You must go into the world outside the forest and gain a broader understanding of the world.
Therefore, if you wish to transfer your class, you must leave the Elven Forest and go to Aden, the kingdom of Humans. The nearest place you can go is the land called Gludio in the south. A guild was secretly established there by some Dark Elves. You'll meet the Grand Masters there, each of whom are very high-ranked trainers. If you carry out all the tasks they ask of you, you can transfer your class.
By the way, there are two villages in the Dark Forest that you can visit. The first one is Gludin Village. Follow the road that leads towards the School of Dark Arts for quite a distance, you'll eventually arrive at the village. And the other is the Town of Gludio. You can get there by going through the Neutral Zone. Although you can get to the Town of Gludio quicker, you may run into some trouble with the Elves in the Neutral Zone.
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