Carnival Cards are cards that are used as currency in the Fun Bazaar. The player can earn them by completing minigames, finishing Star Battle Arena, playing on Party Mode, or anything that is curricular in Mario Party 8.
After completing the Star Battle Arena, the player wins 200 Carnival Cards. In Party Mode, the player wins double the number of cards as the turn number they chose at the start (for example: a 50-turn game results in 100 Cards). When playing other modes, the player wins only 1 card per minigame played. At Test for the Best, the player wins 10 cards from the minigames. A good score (6000-7499) leads to 10 extra cards, and a great score (7500+) equals to 20 extra cards.
The Carnival Cards only appear in Mario Party 8; however, Mario Party Points from later games work in a similar fashion.