Private leagues are a way to create custom temporary leagues for a group of players.

When creating a private league, you can choose a league type to base it on. This can be a variation of the current challenge league, or one of the permanent leagues. Your league has a base cost and you may increase the number of players or the duration of the league. You may also choose additional modifiers to make the league more challenging for no extra cost. You may also choose an event league type for your private league. Event leagues are only available occasionally (and for a fixed period), but can be created for free with a restricted set of modifiers.