classic pay 2 win game, don't spend at all unless you decide to spend big. even then, it wont guarantee you enough luck to be high rank. the late game (5M+ power) relies heavily on luck from getting hero copies, other people can get lucky 13 star on every meta unit, while you get nothing. this is coming from the consistent rank 3 player who got overshadowed by other players because all i get from my last 300 summon are literally Epic heroes or 4 stars, i just have to quit spending and playing.