Yamaguchi opening rule

It was developed by Japanese player Yusui Yamaguchi.

The sequence of moves implied by the rule follows.

It gives an average variety of new playable variants in a good number of openings, but some of them (13ths and some others) don't become playable.

More, this opening rule doesn't protect players from a 11D-draw variants.

[1][2] This opening rule was official opening rule for Renju World Championships and Renju Team World Championships from 2009 to 2015.