The game suggested me to review it. Currently at stage 30. For every second stage I had to watch an ad. I've spent more time watching ads than playing. Nothing special in the game. For each level completed you get 10 coins which you could spend on buying skins, each worth 1000. There are a total of 12 skins or as the game calls it, characters, but there is no difference between them. No ammo limit, no weapon upgrade, nothing. I'll make an update if there is anything else 🤷‍♂️