Everybody keeps complaining about how hard it is to advance as a f2p player but Supercell has done an amazing job at making legendaries more obtainable through challenges and chests and what not. I havent spent a dime on this game and after a couple of matches a day in my spare time have advanced to legendary arena. I found spell valley the hardest to get out of lol. I mean yeah, the wait times are a little long for some chests but all in all if they werent the game would be broken. If anything Id like to see a better trainer. Right now he is horrible. I think you should be able to customize his difficulty and the cards he plays so you can test your deck on what people are actually using. Hope this gets added. Other then that, a very, very well put together game.
UPDATE 3/31/17
Supercell please please please nerf the elite barbarians
Platypus Hero XD about Clash Royale, v1.8.1