it's shit, completely dependent on spy cards.
i don't know how far into it you are, but the card game is entirely reliant on spy cards - don't even try to play the quest battles if you don't have any spy cards. all other cards are literally meaningless and worthless.
otherwise, the rules are - you have three types of cards - rock, paper and scissors that can attack and be attackked by different cards. the goal is to beat the opponent with as little score as possible, so you can conserve cards for the next round. so, you draw like 20 cards for the 3 round game. if your opponent brings cards totaling 15 points, you should try to win with 16 points, not with 25, so you can have more cards for the next round. another tactic is to get your enemy to expend his cards in round one so you can roll him in the other two rounds.
it's fairly fun, the spy cards ruin the game, unfortunately