Copyright (c) 1988 Scott Marley and Philip Cohen

This game is played on a 8x8 square board, with the following setup:

PORTS - Black's port is cell a1, White's port is cell h8.
TURN - Each player, on his turn, moves one of his stones.
MOVE -  Each stone moves like the Chess Queen, any number of empty cells, in any direction (orthogonal or diagonal). 
A stone cannot enter its own port.
CAPTURE - Any stone staying on a cell in the move range of 3 or more enemy stones is captured.
GOAL - Wins the player that moves a stone into the enemy port, and the other player is unable to capture it on his next move.

An example

After Black's b4-c5, White can move his stone at g5 to cell [1], capturing c5, since there are 3 white stones that can move there, namely, g1, h5 and e7.