When the Clan War Leagues begin, there will be a two-day sign-up period.
Clan co-leaders and leaders can assign bonus League Medals as a reward to the best-performing members of the clan.
Players receive League Medals as rewards for their participation in the War League, and these medals can be spent on various items.
If your clan places last and you are in the lowest league, you will not be demoted.
At the end of the War League period, the best performing Clans in the group will be promoted to the next higher league, while the worst performing Clans will be demoted to the next lower league.
The Clans will begin a round-robin tournament, where each Clan battles every opposing Clan once.
After the group has been set, the War League begins, and lasts for eight days.
Once a Clan has signed up, they will be placed in a group with seven other Clans in the same league as the Clan.
Once every season, there will be a two-day League sign-up period, where Clans can sign up for the War Leagues.
Each League runs once per season, at roughly the same time as each other.
The highest leagues offer the biggest rewards and show that the clans in them are the best of the best! Supercell described Clan War Leagues as " Eight Clans Enter, One Clan Leaves" in a youtube video.
In War Leagues, groups of 8 clans compete against each other to progress through the leagues, as well as win rewards.
Clan War Leagues is a feature that was added in the Version 11 update on October 23rd, 2018.