e9: White takes the other obtuse corner in order to strengthen the southwest edge. Now White has both obtuse corners, which is strong, but they’ve left Black with two j9-like acute corners, which is also very strong. Even though would still have been attacking thanks to , White elects to play on the short diagonal. This is more strongly attached to the southwest, but invades less of Black’s space along the southeast edge.
h6: Probably the best place for Black to cut through the short diagonal.
j11k11j12k12k10l8l10m9m10 (Diagram 315): Continuation of this acute corner pattern. Black may be playing the clock with m9m10 (under some time controls, players get extra time when they make a move, so occasionally you will see seemingly unnecessary sequences played because a player is trying to bank time for later).
g10: Exactly fits the edge of the board with Template A-4.
f12: Perhaps White wants e11c12d13. The extra stone on c12 would help connect connect to the southwest with less space, and there’s also the potential follow-up of f10f11 for additional territory. However White’s ignoring the principle that you should avoid weak blocks in the middle of your opponent’s connecting area. This leaves open the possibility of a minmaxing response, if Black can find a good one.
g8: Minmaxing move. Black can keep as a threat now. For example if e11h11h10g11 then Black still threatens or .
h10: White still wants that territory on by cutting off the risk of Black playing , perhaps expecting the response e11c12d13.
d8 (Diagram 316): Instead of the “obvious” e11 (which leads to the followup c12d13), Black keeps multiple paths open through this minmaxing move. If White cuts off directly with c10, Black can respond with e11, and there’s no point in White playing c12d13. Notice how much better this outcome is for Black as compared to e11c12d13, since this way Black gets the stone on d8.
e11: Instead of c10, White responds with e11. But Black has a second threat, as we’ll see next.
d11c10e10: This is the other threat of Black’s move 23. White must block from connecting to the southeast, hence c10. Black’s e10 is forced.
h4f5h5f7: White will eventually want to block from connecting to . Doing so will send the game towards the northern obtuse corner. So White first tries to get some territory in the area by threatening to cut off from the northwest. Black’s responses keep the group connected to the northwest, with Template L-5a.
i7i8k7j7: Forcing moves by Black. Notice how the game is moving towards the northern obtuse corner. Now we’ll see if White’s territory gained on moves 28–31 will be enough.
l4: Note that k6 would not be connected to the northeast edge for White. Alternatively, if l5, Black gets a winning second-row ladder through k6j6k5 and either k3m2 or l3j4j3k3, with and escaping any second-row ladders.
j10i10: High intrusion to j9. Serves as a ladder escape after j6k6k5m4.
j3: With nearly connected to the northwest edge, White tries to salvage some territory but risks being undermined.
l2l3k3j6l5: Black begins to undermine White with the connection to the northwest.
g11 (Diagram 319): White tries to resist the obvious move k7 by threatening to cut off from the southeast edge.
h9: Black plays a minmax type move in response. This group isn’t totally connected to the southeast should White play h12, but there are strong responses for Black.
k7: The intrusion on move 20 has really only strengthened Black’s position. White plays k7 now.
l8l7: With this move Black has ensured that is now strongly connected to the southeast, since can be used to initiate a ladder-escape fork for a third-row ladder. also threatens to connect to , forcing the White response and handing the initiative back to Black.
j7k6: Black takes territory. Note the Trapezoid template.
g6: Note that i6 could be connected to after White’s response j5. If White plays h4, Black responds with e6, leaving them in a very strong position, for example e5d6e2e3f2f3g2h3g3g4.
e7h4g3i2: Here White makes it a tad harder for Black to connect the – group to the northwest edge. Now is part of the area Black needs to connect this group to the edge—note how this hex must be free for e2f4g4f3 to work for Black. Keep this sequence in mind, the endgame will revolve around it.
h6: White blocks Black from playing at , which would win the game (since and are connected to the northwest edge and is connected to the southeast).
d11swaph6 (Diagram 322): Unorthodox opening. It’s third-row ladder escape, but it’s off the short diagonal so it isn’t as strong as it looks. White elects to swap. The response is in the obtuse corner while also serving as a classic block.
e4j9f8: The players occupy the remaining corners. Note how is connected to the southwest edge thanks to .
c4c2d2: Black attacks White’s acute corner. A standard corner pattern (low intrusion, old response) plays out. White is still quite strong towards the southwest edge. Black now has second- and third-row ladder escapes along the northwest edge.
d6: This move coordinates with , being a bridge move away. However it doesn’t really attack Black very much, lying very close to White’s southwest edge, which was already quite strong. A more aggressive move may have been appropriate here.
e7 (Diagram 323): Black keeps open options to to approach the southeast edge. They can either go around the north side of from , or the south of from this stone. This stone also cuts off from it’s previously strong connection to the southwest edge—White will have to spend a move if they want to save it, so we could consider this a weak block.
g5: White responds with a weak block of their own, threatening to cut off either or from the northwest edge. This gives White a second threat to cross the board, in addition to the one going through . What’s more, should Black attempt to block from the southwest with d9, White can connect it with g6f5g3h4 (Black can’t break the fourth-row ladder at , it won’t connect to the northwest) g4.
i6: Black plays a minmaxing response. This strengthens Black’s connection to the southeast while staying nearly connected to the northwest. White could attempt to block the latter by i5 but Black can deflect with h5i3h4h3f4g4e6f7d9 making use of .
h9: Black’s central group is more weakly connected to the southeast, so White attacks it here.
g6 (Diagram 324): Minmaxing again. By connecting the central stones together into a single group, Black guarantees they are connected to the northwest. This also serves as a strong base from which to connect to the southeast by adding the threats provides.
d11: With threats coming from both and the – pair, White blocks a bit further back in order to meet both threats simultaneously.
f10: Black plays a double threat in response, the – group can be connected to or the edge by either of:
Note that these threats, as well as the connection of to the southeast, depend on using to escape ladders.
i10: With the importance of to Black’s threats, White blocks its use as a ladder escape. Another approach might have been to play f9, which cuts off the threat of d9 through the response d10, however Black can play g8g9i8i9j8i11k10k11j11i13 and then use to get a switchback and connect.
d9 (Diagram 325): With this move, Black has strongly connected the central group to through either or . Note how these threats don’t overlap. White’s only attempt to block from the southeast is f11, yielding a second-row ladder, but Black can play the ladder fork b12.
i3j4: One last attempt by White but the game is over. After k2h4h3f4 Black would be connected to the northwest. White resigns.
g4: This stone is attached to the northwest edge by Template A-4 or Template B-4. Black has played too close to their edge and has not occupied a corner.
h9: White plays further out. Note that this move is four bridge moves (i10 j11 k12 l13) away from the east corner.
j9j11l11l10k10k11i11j8: Acute corner pattern sequence. Black now has second-, third- and fourth-row ladder escapes (the higher ladders will cascade through into second-row ladders which can be escaped by ). White’s is connected to the northeast edge.
f8: This move is threatening connection towards Black’s southeast edge. For example e10g9f11g10 or f9e9d11e10 and Black has a fourth-row ladder escaped by and . But it’s not strongly connected: White could block with d12.
g6: White would rather attack the weaker link in Black’s connection, between and . This move is attached to the northeast edge: the seventh-row ladder h6g7h7g8 is escaped by the – group. Lower ladders that could result from other blocks are also escaped along with the – group (for example, h6g7h8h7j6i7j7i8l7k8l8k9).
f6 (Diagram 327): Black must try to stop White on the southwest side of the board.
e9f9e10f10f7: Before pushing through at f7, White gets some much needed territory by threatening to cut off from the southeast edge.
d8e8c10c11a12: Black’s tries to defend, but can only hold White to a second-row ladder. An alternative sequence, d8e8d10d9b10, holds White to a third-row ladder. With either of these ladders, White can use to switchback and connect through .
b7b12: Playing the far obtuse corner is the usual response here.
c11: Trying to block a potential third-row ladder coming from .
g5 (Diagram 331): White neglects to save the ladder escape! Of course there’s always the option of breaking at or . Alternatively, White can deflect: if b8c8b9c9b10c10b11c12, then Black is in trouble. There is no third-row escape along the southeast edge, and of the two points to break to, and , neither looks very good.
h5g7: Black blocks from the northeast edge. White steps around the block.
b8c8: White is fine to play the ladder given the options discussed in the comment on move 20.
e8: This cuts off the option of breaking at . It also threatens to cut off from : if White connects to the southwest with b9 then f6f5g6.
c12: White cuts off from the southeast, effectively starting a third-row ladder. As mentioned above, Black only has two points to break to: and .
c10b9: With all but connected to the southwest, Black settles for connecting to through this weak block.
k6: Desperation play to block from the northeast edge.
g10: An excellent finish. cannot be separated from (which connects to the northeast edge via ): if h10 then g12g11f12e12f11i13i11. To block from , Black will have to play either g8 or g9; or maybe try to use a weak block against . There are numerous variations but none work for Black, for example: g8i6j6i7k8i8m8l7. Black resigns