The -yamaguchi option specifies Yamaguchi openings rule. This rule was introduced by Japanese meijin Yamaguchi Makoto.

The Rules of Renju

Here is a synopsis of the rules for Renju. A more complete rule set can be found at: http://www.renju.net

Object of the Game

On a 15x15 board, each player tries to create a line of 5 (or more) pieces of their color while trying to prevent their opponent from doing the same thing.

Movement Rules

          A B C D E F G H J K L M N O P 
      15  . . . . . . . . . . . . . . .  15
      14  . . . . . . . . . . . . . . .  14
      13  . . . . . . . . . . . . . . .  13
      12  . . . . . . . . . . . . . . .  12
      11  . . . . . . . . . . . . . . .  11
      10  . . . . . . . . . . . . . . .  10
       9  . . . . . . . . . . . . . . .   9
       8  . . . . . . . . . . . . . . .   8
       7  . . . . . . . . . . . . . . .   7
       6  . . . . . . . . . . . . . . .   6
       5  . . . . . . . . . . . . . . .   5
       4  . . . . . . . . . . . . . . .   4
       3  . . . . . . . . . . . . . . .   3
       2  . . . . . . . . . . . . . . .   2
       1  . . . . . . . . . . . . . . .   1
          A B C D E F G H J K L M N O P 

         Figure 1 -- Initial Renju Board

On your turn, you place a piece of your color on the board. There are a number of movement restrictions (I call them "rituals") for the first 4 moves.

Players are initially referred to as "tentative Black(Eks)" and "tentative White(Ohs)".

Move#1.

tentative Black makes three moves "move1,move2,move3". Move1 places a black stone and must be 'H8'. Move2 places a white stone and is restricted to [G-J][7-9]. Move3 places a black stone and is restricted to [F-K][6-10].

Move#2a.

tentative White has option to swap colours.

Move#2b.

White makes an unrestricted move

Move#3.

Black proposes two moves "move1,move2" as Black's Choice. The two moves made must be asymetrical in at least one aspect except relative distance from the edge of the board.

Move#4.

White makes two moves "move1,move2" where "move1" is one of the moves proposed by Black on Move#5 and move2 is an unrestricted move.

Subsequent moves are unrestricted. However, the victory conditions for White and Black differ a bit...

Black wins...

by making a line of exactly 5 stones of his colour.

White wins...

by making a line of 5 or more stones of his colour.

or if Black makes a "double three"

or if Black makes a "double four"

or if Black makes an "overline"

 

Yamaguchi openings rule

1. First player puts 3 stones (from 52 openings, like with RIF standard rules + new 26 large openings), and at the same time, suggests how many alternative 5th moves to be made.
2. Second player decides to swap or keep as white and plays the 4th move.
3. When black plays the 5th move, he/she needs to play as many alternative 5th moves as suggested by tentative black when opening the game.
4. White chooses one of the 5th moves, and plays the 6th move.
5. Continue as RIF standard rules (with forbidden moves rule for black).