The main objective of the game is to claim more gems than your opponent, by finding ways to push cards to gems. To start the game you have to pick a card from your selected deck. Each Card has one or more arrows pointing in a certain direction; the arrows indicate where you can push another card to. The game ends when all the center squares are full or when the gems are locked.
- You can't put a card on a gem, you have to push one to the gem.
- You can't place a card outside of the center squares, but you can push one there.
- You can't push a card against a card with an opposing arrow.
- Cheater Cards can be also be used.
- Beeto Buster (Change your opponent's hand to all Beetos.)
In King of Cards, the inhabitants of the Valley are taking part in a competition of Joustus, in places such as the Card Shack. The title of King of Cards is awarded to the best tactician among them. King Knight, with the help of the Card Bard, partakes in the competition, hoping to become a true king.
Among the participants and other casual players are:
- Farrels (Skill: C)
- Molly (Skill: C)
- Juice Maid
- Magicist (Skill: B)
- Leo (Skill: C)
- Grizzled Seer
- Goatician (Skill: A)
- Playing Kid
- Horse Rogue
- Black Knight