(;AP[HexGui:0.10.GIT]
C[2021/09/10

Black\: Sarah
White\: Frank

Handicap\: 1

White wins.
]
FF[4]GM[11]PL[B]SZ[13];B[c12];B[g7];W[f9];B[e9];W[e11];B[d11];W[e10];
B[d10];W[f5];B[f7];W[e8];B[f8];W[h4];B[i4];W[h5];B[i5];W[k3](;B[h7]
C[Eric\: better j2, see next variation.];W[j2];B[e5];W[f4];B[e4];W[f3];
B[e6];W[e3];B[c4];W[c3];B[d3];W[e1]
C[Eric\:

j2 has a connection to the M-edge and Black's i5+g7 group has a connection to the 13-edge, so both of those connections might-as-well be achieved.  Thus, the https\://www.hexwiki.net/index.php/Interior_template#The_long_crescent from j2 to f3 means there is an invisible white piece on i3 and an invisible black piece on h2\: White's virtual connection means Black can't get _more_ than such a ladder escape, and Black playing such a ladder escape is absolutely forcing against White's connection.

As a result of Black's h2 (or g2 or i2), whiteE1 is locally bad (though White is probably losing anyway, and it might also be what I would've tried).  Black has a semi-connection to the 1-edge (via E2) which after blackH2, doesn't interact with anything else (contrast with how, for example, the semi-connection at https\://hexworld.org/board/#11,d6f5d7f7g6 interacts with E7), so Black can punish E1 by giving D3 another such (i.e., not interacting with anything else) semi-connection to the 1-edge.  The locally-best way to do that here is B5.

In fact, B5 wins easily here, since it also connects to Black's central group, via  https\://www.hexwiki.net/index.php/Interior_template#The_span .]
;B[d2];W[d1];B[b2];W[c2];B[a4];W[b4];B[a5]
C[Eric\:

b5 still wins, as explained in my move-29 comment.];W[b5];
B[a6];W[c8];B[b7]C[Eric\: good
];W[b6];B[a7];W[d6];B[c6];W[d5];B[e2]
C[Eric\: losing. d4 is now an easy win for White.

Black d4 was winning, for the same reason as  36. b5  was winning.

Until move 49, both player's moves are losing and whoever plays at d4 wins.]
;W[f1];B[f2];W[g1];B[h2]C[Winning.];W[h3];B[g2]
C[Eric\: Losing. d4 was still winning for Black.  (See my move-46 comment.)]
;W[d4]C[Eric\: finally];B[resign])(;B[j2]
C[Eric\:


Due to how far White's E10 stones are from the M-edge, I would've been much more confident defending in the M13 direction than attacking in the A1 direction.

Note that now, White only has a height-2 escape in the M1 corner.]
))
