Here is your main screen, you can check on it your personal profile, Start Battle, challenge other players on different Arena and when your reach level 5 you will be able to manage your tower. Arenas are the battlefields where players compete. They are unlocked as you increase your Trophy count. Each Arena, besides the final Arena: Mythical Arena, will unlock new Cards. You receive more rewards like Cards and Golden Rabbit in Chests with a higher Arena level. You can also solve some Puzzle and quest in order to get more reward. Do not forget that certain features are unlocked when the player reaches new Arenas rather than Experience levels.