During the fight with first form Freiza with Nail if you can manage to do 10 or more damage to Freiza (cheat or get incredibly luck with your cards) it will count as Nail stalling Freiza for longer than in the manga/anime. If you are able to stall Freiza you will be able to have an extra wish granted when the characters summon Porunga (the Namekian Dragon). Your extra wish can either be for the Moon/Tail card or for the Porunga Card. You might want to grab the Moon/Tail card if you used the other one already for a powered up Gohan for the Freiza or Super Saiyan Vegeta fights. Otherwise grab the Porunga card, if used in battle it allows you to have 3 wishes: 1 - transforms all the cards in your hand to Z/Z Ki cards, 2 - Gives all of your characters 1 level up, and 3 - halves all enemies' HP (note: through what I believe to be a glitch you can do this several times bringing enemies down to 1/8 or 1/16, etc. of their full health - but be warned you can go too far and the game will freeze)