Tournaments are a way for you to really prove how great of a Matcher you truly are and they unlock once you've reached 1,100 Trophies.
They range from 8 players and up to 64 players, combined with different rules, game modifiers, and entry requirements (such as specific booster levels or a coin fee). They also offer great prizes such as event points, tournament cups, and even boosters! All prizes and game rules can be seen in the 'i' and gift icons in the tournament banner.
When joining a tournament, you will initially be paired with a random player, regardless of the booster or perks chosen to play with. The tournament will wait to fill up all its seats before starting the game for all the contestants.
Each tournament is divided into blocks of 4, so if you win the match against your opponent, the next opponent you'll play against will be the winner of the match in the same block as you.
Before joining a tournament, you will use the same booster and same perks throughout the entire tournament without the ability to change midway through.
It is important to know that individual matches in tournaments also give you stars, and trophies, unless the match is unranked. Unranked matches will show an unranked icon in the banner.