The loading screen tips recommend using Prize Fight to grind. However, as the difficulty steadily increases, it's actually a TERRIBLE place to grind up low-level fighters. Many mobile games have once-a-day/high-energy daily events for gaining experience through drops of unusable/bad characters that give massive EXP. I'd like to see a system like this implemented. The maps could be small and only playable once per win/give these EXP character drops through treasures. Perhaps each weekday could drop EXP characters for each element. You could fill out the weekend days with similar maps but with Canopy Coins as rewards.