Chunin exams

Once in every while (6 months or so), ninja from all different villages compete in a series of tasks in order to become a Chunin. In the anime, only Fire Country/ Konoha has been seen to hold such events, though it is mentioned that the Village Hidden in the Mist once held brutal Chunin exams in which all Genin are pitted against eachother in a last-man-standing-wins brawl to see who would become a Chunin, earning it the nickname "Village of the Bloody Mist". It would also be worthwhile to mention that Zabuza participated in this brutish event when he was not even of age, and yet he still killed everyone else (because of his actions, this practice was discontinued as a way to judge Genin for Chunin). As seen in Anime, the exam includes three trial stages where Genin are weeded out. The proctors in the anime are Morino Ibiki, Mitsarashi Anko, Gekko Hayate (until he was kiled by Baki) and the Hokage in the final test. Morino Ibiki held the written exam part while Anko held the Forest of Death test. The Hokage and the various Jonin that accompanied the Genin hold the last part of the test which are preliminary rounds (if needed, only to eliminate Genin when too many remain) and 3 months later (to give the Genin time to train), the final rounds, where Genin face each other off until one is unable to fight, gives up (i.e. Shikamaru), or is dead.