Since version 2, the League has been Pokémon Duel’s main mode: ranked online matches against other players. Here is how it worked, based on Serebii.

Carmonte Island.

Matches

Each match earns keys to open locked boosters: one for a loss, three for a win. Boosters can be stored and also opened with gems. You face players in the same league, and your rating goes up or down depending on the result and your opponent’s rating.

Ranks

RankRating
Starting rankUp to 1,300
Trainer1,500 and above
Leader1,700 and above
Elite1,900 and above
Champion2,100 and above
Great2,400 and above
Ultra2,700 and above
Master3,000 and above
LegendBeyond

Ranking up unlocked new figurines in League boosters. The rank names are those of the English version.