GGN Examples

Practical examples demonstrating General Gameplay Notation v1.0.0.

Basic Movement Patterns

Simple Move

{
  "C:R": {
    "a1": {
      "a4": [
        {
          "must": { "a2": "empty", "a3": "empty", "a4": "empty" }
        }
      ]
    }
  }
}

Rook at Square a1 has the movement capability to reach Square a4 when all intermediate Squares and the destination are empty.

Move or Capture

{
  "C:R": {
    "a1": {
      "a4": [
        {
          "must": { "a2": "empty", "a3": "empty", "a4": "empty" }
        },
        {
          "must": { "a2": "empty", "a3": "empty", "a4": "enemy" }
        }
      ]
    }
  }
}

Two distinct movement possibilities: rook can perform board-to-board Displacement to empty a4 OR board-to-hand Displacement (Capture) of an enemy Piece at a4.

Special Chess Moves

Castling

{
  "C:+K": {
    "e1": {
      "g1": [
        {
          "must": { "f1": "empty", "g1": "empty", "h1": "C:+R" }
        }
      ]
    }
  }
}

King in Enhanced State (+ modifier) has the movement capability to castle kingside if path Squares are empty and rook is in position.

En Passant

{
  "C:P": {
    "e5": {
      "f6": [
        {
          "must": { "f6": "empty", "f5": "c:-p" }
        }
      ]
    }
  }
}

White pawn has the movement capability to Capture en passant if f6 is empty and f5 contains a vulnerable black pawn in Diminished State (- modifier).

Pawn Promotion Zone

{
  "C:P": {
    "e7": {
      "e8": [
        {
          "must": { "e8": "empty" }
        }
      ],
      "d8": [
        {
          "must": { "d8": "enemy" }
        }
      ]
    }
  }
}

Pawn at e7 has movement capabilities to advance to e8 if empty or diagonally Capture to d8 if occupied by enemy Piece.

Drops and Reserves

Drop from Hand

{
  "S:P": {
    "*": {
      "e5": [
        {
          "must": { "e5": "empty" }
        }
      ]
    }
  }
}

Pawn in player’s Hand has the movement capability for hand-to-board Displacement (Placement) to e5 when the Square is empty.

Drop with File Restriction

{
  "S:P": {
    "*": {
      "e4": [
        {
          "must": { "e4": "empty" },
          "deny": {
            "e1": "S:P", "e2": "S:P", "e3": "S:P",
            "e5": "S:P", "e6": "S:P", "e7": "S:P",
            "e8": "S:P", "e9": "S:P"
          }
        }
      ]
    }
  }
}

Pawn Placement to e4 has the movement capability when Square is empty and no other unpromoted pawn (in Normal State) exists on the e-file.

Complex Constraints

Xiangqi Cannon Capture

{
  "x:c": {
    "b2": {
      "b8": [
        {
          "must": {
            "b3": "empty", "b4": "empty",
            "b5": "empty", "b6": "empty",
            "b8": "enemy"
          },
          "deny": { "b7": "empty" }
        }
      ]
    }
  }
}

Cannon has the movement capability to Capture by jumping over exactly one Piece: path Squares must be clear except for one platform Piece at b7.

Selective Capture Restriction

{
  "C:R": {
    "a1": {
      "a8": [
        {
          "must": {
            "a2": "empty", "a3": "empty", "a4": "empty",
            "a5": "empty", "a6": "empty", "a7": "empty",
            "a8": "enemy"
          },
          "deny": { "a8": "c:k" }
        }
      ]
    }
  }
}

Rook has the movement capability to Capture any enemy Piece at a8 except the black king (specific Name exclusion).

Knight Jump

{
  "C:N": {
    "b1": {
      "c3": [
        {}
      ]
    }
  }
}

Knight has unconditional movement capability to c3 with no environmental constraints required.

State-Aware Movements

Enhanced State Pieces

{
  "C:+R": {
    "a1": {
      "a4": [
        {
          "must": { "a2": "empty", "a3": "empty", "a4": "empty" }
        }
      ]
    }
  }
}

Rook in Enhanced State (+ modifier) has movement capability constrained by path requirements.

Diminished State Capture

{
  "c:p": {
    "d4": {
      "e3": [
        {
          "must": { "e3": "empty", "e4": "C:-P" }
        }
      ]
    }
  }
}

Black pawn has the movement capability to Capture en passant only when white pawn is in Diminished State (- modifier), indicating vulnerability.

Multiple Destinations

{
  "C:N": {
    "e4": {
      "c3": [
        {
          "must": { "c3": "empty" }
        }
      ],
      "c5": [
        {
          "must": { "c5": "empty" }
        },
        {
          "must": { "c5": "enemy" }
        }
      ],
      "d2": [
        {
          "must": { "d2": "empty" }
        }
      ]
    }
  }
}

Knight at e4 has movement capabilities to multiple destinations, each with their own environmental constraints and possibility variations.

Cross-Style Games

Mixed Piece Systems

{
  "C:Q": {
    "d4": {
      "h8": [
        {
          "must": {
            "e5": "empty", "f6": "empty",
            "g7": "empty"
          }
        }
      ]
    }
  },
  "x:m": {
    "b1": {
      "d2": [
        {
          "must": { "d2": "empty" },
          "deny": { "c1": "enemy" }
        }
      ]
    }
  }
}

Chess queen and Xiangqi horse coexisting with their respective Style-specific movement capabilities.

Advanced Patterns

Double Negation for Allied Piece

{
  "S:L": {
    "c3": {
      "c4": [
        {
          "deny": { "c4": "enemy", "c4": "empty" }
        }
      ]
    }
  }
}

Lance has movement capability to c4 only when it contains an allied Piece (neither empty nor enemy, evaluated from Active Player perspective).

Conditional Path

{
  "C:B": {
    "a1": {
      "h8": [
        {
          "must": {
            "b2": "empty", "c3": "empty", "d4": "empty",
            "e5": "empty", "f6": "empty", "g7": "empty",
            "h8": "empty"
          }
        },
        {
          "must": {
            "b2": "empty", "c3": "empty", "d4": "empty",
            "e5": "empty", "f6": "empty", "g7": "empty",
            "h8": "enemy"
          },
          "deny": { "h8": "c:k", "h8": "c:q" }
        }
      ]
    }
  }
}

Bishop has two distinct movement possibilities to h8: Displacement to empty Square, or Capture of any enemy Piece except king or queen.

Important Notes

Evaluation Context

All enemy evaluations in these examples are from the Active Player’s perspective - the player whose Turn it currently is, as defined by the protocol.

What GGN Represents

GGN encodes Mechanically Possible Moves (also called Pseudo-Legal Moves):

Movement capabilities: Nominal abilities of Pieces based on Name, State, and Style attributes
Environmental constraints: Board conditions that must (or must not) exist for movement capabilities to be realized
Movement possibilities: Distinct combinations of capabilities and constraints for reaching the same destination

What GGN Does Not Represent

GGN deliberately excludes game-specific concerns that transform Mechanically Possible Moves into Legal Moves:

Check State restrictions and Terminal Piece protections
Historical conditions (castling rights timing, en passant temporal requirements)
Turn-specific constraints beyond basic alternation
Victory/defeat conditions and Terminal States
Move execution mechanics and Action sequencing
State transition consequences and cascading effects
Competitive interpretations and rule-specific legality

Move Hierarchy Position

As defined in the protocol and glossary:

Protocol-Valid Move
    ↓ (+ piece movement capabilities)
Mechanically Possible Move / Pseudo-Legal Move  ← GGN operates here
    ↓ (+ rule system constraints)
Legal Move

GGN operates at the Mechanically Possible Move level, encoding what Pieces can do geometrically based on their attributes, without incorporating game-specific legality rules.

Design Philosophy

GGN focuses exclusively on describing movement capabilities with environmental pre-conditions. Game engines and rule systems handle:

Filtering Mechanically Possible Moves to determine Legal Moves
Move validation against complete rule sets
Move execution and state transitions
Consequence evaluation and competitive interpretations

This separation enables GGN to remain rule-agnostic while providing a foundation for diverse rule systems.