You and your opponent are stranded on an uncharted and unstable island. The landscape shifts mysteriously, and terrain often disappears into the sea.
Your goal is to escape the quicksands--and defeat your opponent--by consolidating the remaining tiles of your shape or the remaining tiles of your color.
Syrtis is played with tiles of four types: light circle tiles, dark circle tiles, light square tiles, and dark square tiles. (They're all square, but they may have either squares or circles on them.) There are also four towers: two light, round towers, and two dark, square towers.
Arrange the tiles according to the process below to form the board. Half the tiles will be drawn randomly; the other half will make the board fair. For an evolving, strategic game, play Syrtis Major: use all thirty six tiles and follow the larger diagram. For a short, tactical game, play Syrtis Minor: use four tiles of each type and follow the smaller diagram.
Mix the tiles face down. Randomly select a tile and place it face up in the position labeled 1. Then turn tiles face up until you find one with the opposite color and opposite shape; place it in position 2. Continue placing a random tile in each odd-numbered position and a tile of the opposite color and shape in the following even-numbered position. (This will make the initial position antisymmetric.) Whenever the face down pile is empty turn all the unplaced tiles face down, mix them, and resume the process. One possible completed board is pictured in the next section.
One player completes the setup by placing all four towers on the board, each tower on an unoccupied tile of its own color or shape. Then the other player chooses whether to play as Light or Dark. Light takes the first turn.
An island is a tile or connected group of tiles that all share the same color or shape. (Groups that touch only at the corners are not connected.) There are light islands, dark islands, circle islands, and square islands.
On your turn you must do exactly one action: move a tower, sink a tile, slide a tile, or pass. At the end of your turn the remaining tiles of the board must be connected.
Move a tower
If you are playing as Light, you may move a light tower to any unoccupied tile in its current light island or circle island. If you are playing as Dark, you may move a dark tower to any unoccupied tile in its current dark island or square island. Other towers do not block such a move.
Sink a tile
You may remove from the board a tile that is (1) adjacent to a tile you occupy, (2) unoccupied, and (3) has at least one open edge. The removed tile may have any color and shape. (Remember that the board as a whole must be connected at the end of your turn.)
Slide a tile
You may slide a tile occupied by one of your towers through any number of connected empty spaces. You may slide the tile in any number of directions, but you may not increase the current width or length of the board, not even in the middle of the turn.
In the diagram, the dashed lines mark the current length and width of the board. Sliding tiles must stay within the box.
Say ‘pass’ and take no other action. Passing does not require you to pass on future turns. A player who cannot perform any other action must pass.
End of the Game
There are three ways to win the game.
You win when all the remaining tiles of your color are connected, or all the remaining tiles of your shape are connected.
If all the tiles of a color or shape are connected when the board is first constructed, the player who places the towers must first switch paired tiles (e.g., 11 and 12 in the first diagram) until this is no longer the case.
If you sink four tiles and meanwhile your opponent has sunk none, your opponent loses the race against the quicksand.
Whenever you sink a tile, announce how many you have sunk since the opponent last sunk one. Keep track by placing the tiles you sink in front of you. Whenever your opponent sinks a tile, move any tiles that are in front of you aside to a discard pile. When you have four tiles in front of you, you win.
This rule thwarts stonewalling and makes ties impossible. The game ends in any of these situations:
- Both players have a complete island at the same time.
- Light and Dark pass on consecutive turns.
- One player passes on four of that player’s turns in a row.
In each case, the player who has most recently sunk a tile wins. In the unlikely event that no tiles have been sunk, the player who took the first turn wins.