ZÈRTZ is the third game in the GIPF project. The game features a shrinking board and an object that promotes sacrifice combinations. Since neither player owns on-board pieces, maintaining the initiative is of fundamental importance.

Rules

Equipment
Playing pieces are 6 white, 8 gray, and 10 black marbles, and (for the standard game) 37 rings, each of which can hold a marble. Advanced players use up to 61 rings.


Setup
Players place the rings on a flat surface and arrange them as a packed hexagon, as regular as possible (the "board"). With 37 rings this is a perfect hexagon with four rings on a side. The marbles go into a shared pool.


Object
The object is to capture four whites or five grays or six blacks, or three of each color. (A simpler variant can be played in which the object is to capture three white marbles or four grays or five blacks or two of each color. See below.)


Dropping
If no jumps are available, the player whose turn it is must drop a marble of any color onto an empty ring of the board, and take a removable ring from the board. A ring is removable if it can be detached by sliding it away on the table surface without displacing other rings. If removing a ring produces a set of one or more rings, called an island, with a marble on each ring in the group, all of these rings are also removed, and the player whose move created the island captures all the marbles on it.

If no ring is removable, the player's turn ends when he drops a marble. If no marbles are available in the shared pool, the player must drop one of his captured marbles instead.


Jumping
If any two marbles are adjacent on the board, and there is room for one to jump the other, landing on a ring immediately opposite the other, a player must jump instead of dropping. When a marble is jumped, it is captured by the jumping player. It is similar to the compulsory jumping rule in Checkers: the player must continue to jump as long as additional jumps by the same ball are possible.

No rings are removed on a turn in which a jump is made.


Variants

Blitz
A short version of the game can be played using only 5 white marbles, 7 gray, and 9 black marbles. In this case, the goal is to capture only three whites, four grays, five blacks, or two of each color. This variant is described in the original edition as the basic rules.


ZÈRTZ+11
This is the game of ZÈRTZ played with 11 extra rings, forming an irregular hexagon with sides alternating between 4 and 5 rings. This is the current standard for serious tournament play.


ZÈRTZ+24
This is ZÈRTZ played with 24 extra rings, forming a regular hexagon with 5 rings along each side. It has been suggested that this will eventually become the tournament standard.