This feature is a high-score challenge where players compete against other players to obtain the most trophies. In a Daily League Event you will be awarded three trophies every time you win a ranked battle and if the match ends in a draw you will recieve two trophies. If you lose the match you will be given one trophy. Once the challenge ends all the players that participated are given a reward which is decided by your rank.
The rewards you recieve in a Daily Battle League Event are determined by your current tier and your placing in the tier. There are seven tiers in total and the higher the tier the better the reward. After the event you will depending on your rank either be promoted to a higher tier or demoted to a lower one. If you rank 1-10 you will get promoted to a higher tier, ranking 11-20 will mean you maintain your current tier, and ranking over 21 or not participating means you face demotion to a lower tier.
Note: You will not receive or lose any medals for the matches you play during the Daily Battle League.