The Shinobi Battle Royale is a free-for-all battle between two shinobi schools, officially sanctioned by the government. It is a old shinobi school tradition, once know as the School Flame Festival. It is said the Shinobi Battle Royale was created to find and elevate Kagura.
Five shinobi students from each school are chosen to take part in a series of battles. The challenged school creates a number of shinobi barriers on campus and defends those barriers from the challengers. If the challenged school manages to fight the opposing school off, they will have the chance to fight back on the opposing school's turf.
In order to win, the school's leader must be defeated. The losing school will be abolished and burned to the ground if the winners choose to do so. Additionally, Shinobi who are defeated at the battle royale lose all right to ever train to become a shinobi for the rest of their lifetime.