1. Object
Obelisk is a two-player strategy board game, and each player controls three stones.
The object of the game is to construct an obelisk by first stacking the pedestal atop the base, and then by stacking the capstone atop this foundation.
The first player to construct their obelisk is the winner, and if a player has no legal moves, the player immediately loses the game.
1.1. Setup
Each player sits across from each other on opposite ends of the game board, with the narrower edge of the board closest.
2. Movement
Players alternate turns, with the player in control of the black stones opening play.
2.1. Forward and Backward
All stones—including the constructed foundation—may only be moved forward (toward the opponent) or backward (away from the opponent) in the following ways.
Forward
Any stone may be moved forward diagonally to an unoccupied adjacent square.
Backward
Any stone may be moved straight backward to an unoccupied adjacent square.
2.2. Constructing the Obelisk
The foundation of the obelisk must be constructed first. To construct a foundation, a player moves the pedestal atop their own base. Once the foundation is constructed, a player may then construct the final obelisk by moving the capstone atop the foundation. However, a player may not move the capstone atop their own pedestal or base prior to constructing the foundation.
Once the foundation of an obelisk is constructed, it cannot be deconstructed, and it moves as a single stone.
2.3. Jump and Ra’s Revenge
There are two special movements, jumping and performing Ra’s Revenge. Even with these special movements, stones can only ever be moved forward diagonally or straight backward.
Jump
Any stone, even a foundation, can jump an adjacent stone or foundation and move to the next square if and only if that square is unoccupied. If any other stone occupies the next adjacent square, a player may not jump an adjacent stone; you cannot jump and construct a foundation, or obelisk in the same movement. Jumping also cannot be used to perform Ra’s Revenge.
Ra’s Revenge*
A player may perform Ra’s Revenge on an opposing player’s base, pedestal, or foundation by moving their capstone—and only the capstone—on top of the opposing player’s base, pedestal, or foundation; however, this player must deconstruct the capstone on their next turn. If this player cannot deconstruct the capstone because there are no legal moves, the player immediately loses the game.
On the turn before a player deconstructs their capstone, the opposing player may move the stone normally, with the other player’s capstone remaining on top of the stone.
To deconstruct the capstone on the next turn, the player must do only one of the following movements, moving the capstone forward diagonally or straight backward:
- Move the capstone to an unoccupied adjacent square or jump an adjacent stone.
- Move the capstone atop a foundation to construct the final obelisk.
- Move the capstone to successively use Ra’s Revenge on an opposing player’s stone.
3. Symmetry
Symmetry must be maintained at all times, and symmetry refers to the arrangement of two or more respective stones on the same horizontal or vertical axis of the game board. As long as any two respective stones are symmetrical after any stone is moved, symmetry is maintained. Movements that would result in no symmetrical stones are not allowed, and if a player cannot maintain symmetry because there are no legal moves available, the player loses the game.
Color Symmetry
To maintain color symmetry, at least two of a player’s own stones must be arranged on the same axis after any stone is moved.
Shape Symmetry
To maintain shape symmetry, at least one of a player’s stones must be arranged on the same axis as the opposing player’s respective like, or matching, stone—base to base, pedestal to pedestal, or capstone to capstone. For example, if one player’s base is arranged on the same axis as the opposing player’s base after any stone is moved, shape symmetry is maintained.
Game Modes
Before beginning gameplay, players choose one of three game modes—open play, bounded play, or balanced play—each of which requires players to maintain a certain type of symmetry.
Open Play
Movements must result in either color symmetry or shape symmetry.
Bounded Play
Movements must result in at least color symmetry.
Balanced Play
Movements must result in both color symmetry & shape symmetry.
Once a player’s foundation is constructed, color symmetry is continually maintained for that player for the duration of the game. A foundation can also maintain shape symmetry with either an opposing base, pedestal, or foundation (but not with the opposing capstone).
The final obelisk must also maintain symmetry, though for open and bounded play, color symmetry would already be maintained by that player’s foundation. For balanced play, however, the obelisk must maintain shape symmetry with any of an opposing player’s stones or foundation.