In terms of making a 'multi-player abstract perfect information game', territory is one of the more obvious themes because it is not mutually exclusive. Phalanx is such a game. However, Phalanx with more than two players thrives on over the board agreements, treaties and treason, in short, the kind of inherent diplomacy that disagrees with turnbased play. You'll have to make a fair number of base-3 boardsegments and get a lot of colored pieces if you want the multi-player experience. Here we cover only the two-player version.

early positionRules
The board is initially empty. There are two players, Red and Yellow, both with a sufficient number of men in their colour. There are also neutral pieces representing cells of the walls.

Group
A group is a number of connected men of the same color. A single man is a group by definition.

Phalanx
Two or more men of the same color in a straight unbroken line are called a phalanx. The line is called the 'line of movement'. A group may contain several phalaxes in different directions.

The basic move protocol
On his turn a player may:
  1. Grow any or all of his groups by one stone.
  2. Move any or all groups that he didn't grow.
  3. Pass.
A pass does not affect the player's right to move next turn. When both players pass on successive turns, the game ends.

Balance
One player places one red man and two yellow men on the board. The other player then decides whether to play Yellow, in which case the opponent places a second red man, or to play Red, in which case he himself places a second red man. In both cases the basic move-protocol kicks in afterwards.

Growth
On his turn a player may grow one man at each of his groups, or at part of his groups or at none at all. It is permitted to connect groups, provided none of the player's groups afterwards has had more than one man added to it. If a single placement connects two groups, it is considered to have grown both of them. It is possible to connect two groups by growing both of them, as long as both placements only touch one another, but neither placement touches both original groups.

Movement
A group has the right to move if it has remained unchanged in the growing stage. The player may move any or all such groups. However if a group by movement connects to another group, the latter loses the right of movement. Thus the order of movement may make a difference.
board
  • Moving a group means moving one and only one of its phalanxes. The phalanx one intends to move is identifed by indicating its 'head' and its 'tail'. The head must be one of the men at either end, the tail may be any other man.
  • The maximum range of a moving phalanx is one less than its number. The head and the (chosen) tail in the diagram identify a three man phalanx which consequently may move up to two cells along its line of movement.

In actual play one moves by leapfrogging, placing the tail in front, then picking up the next man, and so on. A phalanx may be moved less than its maximum range. Moving a phalanx may split a group in two or more parts, each of which has the right to grow next turn.

Restrictions
A phalanx may neither move onto nor over the 'Wall' (see capture) nor onto or over a man of like color.

Capture
  • If a phalanx moves over opponents' men, all men covered are immediately removed as prisoners of the capturing player. The men on top, that perform the capture, return to the capturing player and are replaced by neutral pieces that make up the "Wall", a permanent obstacle for both players.
  • A phalanx may only attack an opposing phalanx on the same line of movement if it is longer than the latter.

Here is a combination. First the smaller phalanx captures a single yellow man, then the 3-men red phalanx eliminates the 2-men remainder. Red captures three men and erects a 3-cells section of the wall.

A phalanx needs not to be 'head to head' with an opposing phalanx it attacks. The only criterion is that it must be longer.

Object
The object of each player is to obtain as large a piece of territory as possible, counted as vacant cells under his control, albeit minus the number of pieces the opponent has captured.

Territory
Two cells are said to be connectable if there exists at least one route of connected vacant cells between them.
At any stage of the game, vacant cells can be divided into three classes:
  • Cells that are connectable with men of both colors. These are as yet neutral.
  • Cells hat are connectable with men of one color only. At the end of the game, these cells make up that player's territory.
  • Cells that are not connectable with men of any color. These are neutral.

End of Game
The game ends when both players pass on successive turns. In over the board play, prisoners then are placed inside the opponent's territory to reduce it with a corresponding number of points. If there'a an applet in the future, it will of course keep track of the score.

The multi-player version
To play with more than two players, you'll have to rely on your skills at making base-3 board segments and providing enough colored pieces. The mechanics basically remain the same. Turn-order balance may be a problem, but not nearly as much as open treaties, secret treaties, treason, collusion and the need for or lack of diplomacy, in short, strategies that interfere deplorably with turnbased play at mindsports.

Just lay out a board, put a single man on each segment and see where it takes you. Board lay-outs can be arrived at by succesive placements of segments by the players, each segment with a player's stone in the middle, or by geometrical placement. It may be compact or have lakes and peninsulas. Anything goes, have fun :) .

History
A concise history of the game can be found in the essay How I invented games and why not.


Phalanx © MindSports