Your Clan is matched into Wars, against other Clans based on your Clan’s Trophy count. In other words, all the Clans in a War will have roughly the same amount of Clan Trophies when the War begins.
In the River Race you will be primarily matched with players that have the same King Level as you, no matter the League their Clan is in. For higher King Levels this matchmaking rule is not as strict, as it is for lower King Levels, meaning you will most likely face opponents that are one or sometimes even two levels lower or higher than you. In other words, a King Level 9 player should mainly be matched with other King Level 9 players, whereas a King Level 13 player will see a more varied range of King Levels.
In order to keep matchmaking times fast and to ensure that players will not get stuck in matchmaking for long periods of time, matchmaking will expand its search using these parameters:
The matchmaking system will also consider your personal performance in Clan Wars when matching you with other players.
Clan War Colosseum
Similar to the River Race, your opponents will be players with similar King Levels, who are also searching for a match in the Colosseum.