Edge template IV2m
From HexWiki
Red can connect the stone marked "1" to the bottom. There are infinitely many related templates, with the two red stones arbitrarily far apart, for example:
and so on. All of these templates work the same way: the stone "1" guarantees Red a second-row ladder, and the other red stone acts as a 2nd-to-4th row switchback, connecting to "1". The following is the best Blue can do (if Blue plays differently, Red will connect to the edge immediately):
