The best thing to do is not to play cards in certain areas for a while. Because the rules change, and become much more difficult to master. Master one towns rules, then move on to another. Mostly all of the players can be challenged at any given time with a few exceptions.

Make sure you save before playing. Sometime near the end of the game when you try to get the phoenix card...you might just have to get lucky. Thats how I did it. Pure luck. The rules are that complicated. Anyone who says they have mastered them and can beat any player at any given time is a liar. Because card games can go either way sometimes.

Also, wait to refine your most powerful cards at the end of the game, once you have obtained every other card. Because if you don't have a strong deck, you won't be obtaining new cards.