It's glitchy and buggy, units will often stand still staring at enemies without attacking even without visible cooldowns, heavy emphasis on pay to win, useful units are locked behind an arduous grind where they'll cost anywhere from 1 to 30 thousand coins, and after clearing any stage, repeating it awards you a whopping 10-30 coins. Not to mention the EXP requirement for units, as a stage rewards you 15 points of EXP while requiring 5000 points to level up. Cash shop is overpriced as well.