The game is setup with the owner chosing his opponent's "base" by placing a block with the "home" sign on the field (which is a map of Japan). When that player loses the game, that area suffers a natural disaster. When Yugi Mutou and Imori played, Imori chose various places in Japan as Yugi's bases because Imori was pushed around ever since he came to Tokyo. Yugi, on the other hand, placed Imori's bases in the sea to prevent damage.
Each player draws 6 blocks and places them in a horizontal line, known as a stack. The sides of the blocks displaying the Chinese characters, should face the blocks' respective owners. Each player draws one block each turn and chooses either to discard it or another block.
The Chinese character on each block identifies the element of the dragon. A player requires three blocks with the same element to summon a dragon.
When a player gets enough blocks to summon a dragon, they can declare that you have summoned 2 dragons, without specifying their elements. They then wait until their opponent has gathered theirs.
When both players have summoned their dragons, they place their blocks Chinese character side-up, allowing both players to see them.
The players then use their dragons to battle. Each element has advantages and disadvantages against other elements.
The player to defeat their opponents dragons wins.
- Yu-Gi-Oh! (Toei) episode 18: "In a Forbidden Game - Show Your Hand"