This is a daily boss fight that will pit you against a boss that will get a permanent buff for every set number of turns. You don’t necessarily have to kill the boss but you have to land as much damage as possible to get a better score. The boss of the day will be weak to a particular element so forming a full-elemental team with the advantage against the boss will allow you to survive longer and deal more damage.
You’ll get reward box after the daily refresh depending on your daily Rank. Your rank will be based on the total damage you inflicted on the boss. The total score of your daily rank will also be tallied for a weekly reward.