Level your cards as much as possible to have a greater chance to win games. After your star card, focus on your strongest card. After playing a couple games obtaining a few cards, modify your lineup. Choose the cards with the best stats as your starters, then level up my top card after your superstar with cards that were earned. Rotate your lineup often to keep the best cards in play. Win tournaments to get the chance to get rare cards as a reward. Only play the regular season games when you have extra energy. During tournaments, you have four rivals that you can play against. After challenging them, you will be allowed to see their cards. If they are very strong back out and challenge a different rival. Only challenge rivals you have a chance of defeating to avoid wasting energy. When you reach a point where you cannot win more tournament games because all opponents are too strong, replay previous single player matches and win them repeatedly for extra cards to level up your existing deck.