Option One:
We have a world wide Chuunin Exams, where we have two stages:
1st- Questions
2nd- One on One Fights.
Option Two:
Each villages can have its own Exams with its own Rules. The Kage can choose the date and everything. But don't worry, if this option is chosen will hold another event. A world wide tournament for all ranks. Genin vs Genin, Chuunin vs Chuunin etc.. and we'll have a "Royal Fight" where the three Kages fight each others.
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