The person who will be supported by the whole family to become a rank 4 noble will have to show wisdom, connections, potential, and promise to prove that they deserve the support.
The way to prove that they deserve the support is to support a gang in the outer city and help that gang gain the largest territory in the outer city. This is what the game is in essence.
Unfortunately, the game has become twisted after many generations. It has stopped being fair, and the outcome of the game has become easily influenced.
Many people have found and used loopholes to get their way in the competition. The best method they found is to pressure each other directly.
Instead of the descendants controlling and supporting gangs to fight for territory, the descendants use their financial and political influence to attack each other.