Again, five-star worthy game yet ruined by unimaginable difficulty once reach higher up level. Well, I guess that is the way some devs work; make player spend some money at first and once we realize it's worthless (cuz it will be an endless spending), we stop. One old player stop, one new player come. So basically devs doesn't lose any. I think it's better to have ads, to get diamond or booster. Or atleast let the player replay lower level, so we don't stuck - wait for days just to clear 1 level