Game Rules: Terni Lapilli

Terni Lapilli is a variation of the classic tic-tac-toe game, where the objective is to align three pieces of the same color. The game is played on a wheel with intersection points. Below are the detailed rules for playing Terni Lapilli.

Objective of the Game

The objective of the game is to align three pieces of your color (red or green) along a continuous line. The lines can be horizontal, vertical, or diagonal.

Board Setup

• The board consists of a wheel with 8 intersection points and a central circle.
• Players can place their pieces on the intersection points or in the center of the wheel.
• Each player has a maximum of three pieces that can be moved after being placed.

Game Components

• Wheel: At the center of the board is a wheel with 8 intersection points arranged along two orthogonal axes and two diagonals. Each point is represented by a small circle.
• Central Circle: The circle at the center of the wheel is also a point where a piece can be placed.
• Pieces: Each player has 3 pieces. One player has green pieces, and the other has red pieces.
• Turns: Players take turns, placing or moving one piece at a time.

Game Flow

The game is divided into two main phases: the Placement Phase and the Movement Phase.

Placement Phase

• Turn Alternation: The first player is randomly selected at the start of the game. Players take turns placing one piece at a time on one of the wheel’s intersection points or in the central circle.
• Piece Placement: During their turn, a player can click on one of the empty circles to place one of their pieces. The pieces are colored red or green, depending on the player.
• Placement Conditions: Circles can only be occupied once. Once a circle is colored, it cannot be used again during the placement phase.

Movement Phase

• Movement Begins: Once both players have placed all their pieces (3 per player), the movement phase begins.
• Piece Movement: In this phase, players, on their turn, can select one of their already placed pieces and move it to an adjacent empty circle (either along the axes or the diagonals).
• Movement Conditions:
  • A piece can only be moved to an adjacent, unoccupied circle.
  • A player can select a piece only if there are empty adjacent spaces and if it corresponds to the current turn’s color.

Victory

• Victory Conditions: A player wins the game when they manage to align three pieces of the same color in a straight line. The lines can be:
  • Horizontal (on the same row),
  • Vertical (on the same column),
  • Diagonal (from one corner to another).
• Victory Notification: When a player wins, the message "Terni Lapilli" appears in the center of the board, signaling the end of the game.

Special Mechanics

• Piece Selection and Movement: During the movement phase, players can select a piece by clicking on it. If the selected piece has empty adjacent circles, the player can move it.
• Game Block: If a player has no available moves because all adjacent circles to their pieces are occupied, the turn automatically passes to the other player without any action.
• Automatic Victory: If a player has no available moves because there are no adjacent empty spaces to move their pieces, the opponent automatically wins the game, even if they have not aligned three pieces.

End of the Game

The game ends when:

• A player successfully aligns three pieces of their color in a straight line.
• A player has no available moves: in this case, the opponent automatically wins the game.

Game Modes

Player vs. Player: This version of Terni Lapilli is designed for two human players, who take turns playing.