Every three weeks, a new season begins, and in order to start a new season, all players have their trophies reseted according to an algorithm. Even though your trophy number decreases, you will receive prizes for this according to the highest League you have achieved during the event!
For each League you achieve, you will receive a special reward:
Master I: 3800 trophies → prize: 15 Packs of Crystal
Master II: 4200 trophies → prize: 20 Packs of Crystal
Master III: 4600 trophies → prize: 25 Packs of Crystal
Grand Master I: 5000 trophies → prize: 30 Packs of Crystal
Grand Master II: 5400 trophies → prize: 35 Packs of Crystal
Grand Master III: 5800 trophies → prize: 40 Packs of Crystal
Champion I: 6200 trophies → prize: 45 Packs of Crystal
Champion II: 6600 trophies → prize: 50 Packs of Crystal
Grand Champion: 7000 trophies → prize: 55 Packs of Crystal
Legend: The highest number of trophies will get the World's First Place! → prize: 110 Packs of Crystal

The Crystals are a new type of currency within the game, and you can use them to increase the level of your cards as following:

- Crystals can be used to temporarily increase 1 level of any of your cards! Imagine you love to play with your level 7 Pirate, but you don't have enough cards to upgrade it to level 8. You can use crystals to upgrade the card to level 8 and play with it for 24 hours! After the time is up, the card will get back to the original level.

- Crystals can also be used to permanently increase the maximum level of a card! So imagine you have fully upgraded Dwarf card, and the maximum level is 13. With the crystals, you can unlock a new maximum level for your card! This means that the Dwarf's maximum level will be 14, and you will be able to acquire more cards and permanently upgrade it with gold!