Sometimes, winning a Battle will reveal a Quest that you can complete in order to gain more Cards to upgrade your Heroes’ Spells.
To undertake a Quests, select a Quest available in the Area and chose a Hero to take the Quest; any Spell Cards gained will go to this Hero. Next, chose which Heroes will provide support, according to the Elements indicated in the Icons. The higher the levels of the Heroes supporting, the greater the bonus applied to the Quest reward.
You can undertake one Quest at a time for no additional cost. However, you can also undertake additional quests with any remaining Heroes you have available by spending Gems.
Each quest takes a certain amount of time to complete; usually 3 hours, 8 hours or 12 hours. This time can be skipped by spending Gems.