Currently, the game has the following leagues (in decreasing order of rank): Emerald, Gold, Silver, Bronze, and Wooden; in the Pioneers Club tournament: Global, Continental, International, National, and City.
The first time you take part in a tournament, you will automatically be placed in the lowest league. If you finish in one of the top spots, you advance to the next league in that tournament. The next time that tournament starts up again, you will start in the same league you finished in. If you finish in one of the bottom spots, you will fall into a lower league in that tournament. The next time that tournament starts up again, you will start in the lower league.
For example, if you finish in first place in the Bronze League in the Circus Boom tournament, you will move up to the Silver League in this tournament. When the Circus Boom tournament comes around again, you will start out competing in the Silver League. If, however, you finish in last place in the Bronze League in the Circus Boom tournament, you will move down to the Wooden League.
Leagues help distribute players based on their abilities and skills in order to increase their chances of victory.