The game is great, but it's a play to earn game. The rank system is broken. At lower rank you may already face players with a very good deck that can special summon a lot of monsters in turn 1. You can't win against those opponents when you are using a starter deck. It's very hard to farm gems in this game, since almost you can get it in rewards in the menu by doing task in the rank game. There is just rank game, no way to farm anywhere else. And you rank up so fast, leading to strong players.