The coming of age ceremony is something every tribal man does. They need to be 18 years old to be eligible to begin. In order to complete it, they are required to kill a beast of 1st degree without any help and bring the proof of maturity back to the tribe.
The coming of age is the first step in Journey of Life and Death. Those that successfully complete the ceremony are awarded tribal name (Not to be confused with "True name" from Warrior Ceremony rewards) and mark of the tribe they belong to.