Chu Shogi Endgame Study #1

In this position, Gote must cover all squares from 12a to 12d to prevent safe promotion, which would cause great trouble later on, most likely nullifying any chance of a Gote win. This can be achieved either by twice defending his 12-pawn before Sente's 12-pawn can meet it, or by single coverage of each of the 4 promotion squares, were Sente to sacrifice a piece for the pawn. Gote will push P-11f and play Ln-11e if Sente does not push his 12-pawn.

Of course, Gote cannot stand to babysit the promotion squares with his lion for too long. Because of this, if Sente indeed quickly pushes the 12-pawn and sacrifices a piece for Gote's pawn, Gote will need to promote his bishop to free his lion up to go elsewhere. For this reason, Sente should look to defend 3i and perhaps divert a couple pieces onto the 3-file. In which order these goals should be met and how many tempi to spend on each task is still in question.

Thus, if Gote frees his lion too quickly, the exchange would be reverse chariot and lance for the bishop, which is less than ideal. Both sides may try to lose a tempo or two in order to gain an edge in this standoff.

Gote's winning chances lie in his ability to free his lion from its temporary defensive duties in a timely fashion and to capture all of Sente's pawns while promoting all of his own. Sente will be very happy to make any pawn for pawn trade. Sente should also not shy away from a step mover for pawn trade if it maintains a stable position.

Sente's most dangerous piece is his side mover. If he can get this piece into an ideal position, it could cause lots of trouble for Gote.

I think top moves to look at for sente are (not in order)

• 12五歩
• 11七歩
• 1十横

I have a clear favorite, but it's best to hear someone else's opinion first.

This was my thoughts before I read your move suggestions:

I would say to protect 3九 right now is highest priority. There are three pieces that can reach there: 横、銅 and 象. If I have to rank the moves I would choose:

1. 3十銅. I think with some support the copper fits for support of the pawns best. 

2. 3十黄. I think it is not so good to expose the side mover that much, but it covers the needed squares and gote would not go for exchange here I think. So it is still a valid option. 

3. 4十象. If sente wants he can go for 2八歩, therefore the move is actually not so good. 

About your moves: I think 11七歩 is a nice one, making pressure and opening the leopard. Pushing the 12歩 immediately is to early in my opinion. 1十横 is a move I don't really get, because I consider the bishop promotion a big threat and think the two pawns are important. Is it the idea to be able to move the 横 to rank 7, while distracting the enemy forces from 12th file? 

11七歩 is easily my favorite (favorite doesn't mean I think it's the best) option. It stops gote from playing 11六歩, which would allow the lion to take the 12-pawn cleanly, and gote can't take the 11-pawn while maintaining proper defense, at least not in any reasonable amount of time.

If for some reason the tempi make it such that that doesn't work, then I really like 1十横. It covers 2 of the 3 potential bishop promotion squares while placing the side mover on its optimal file. Full defense of the promotion squares is most efficient with this move first, then the elephant move.

Of course, gote cannot even consider taking a "free" step mover, were one to line up with one of his ranged pieces, since un-defending the 12-file is impossible.

12五歩 just has to be looked at by default. It clearly isn't best here, much too early, but it should still be considered as a matter of good practice.

Sente cannot defend his pawns if gote plays even in a remotely reasonable manner. Loss of the pawns is inevitable, so it's better not to waste time on them if there are moves to make elsewhere. Besides, gote would be stupid to prioritize taking those two connected pawns right now, when clearly the area of greatest urgency is on the 11- and 12-files.

In conclusion, if sente insists on outright prevention of 11六歩, then 251.11七歩 is the clear choice. If sente doesn't play that, then he can make gote spend 3 tempi to cleanly take the 12-pawn, in which case I favor 251.1十横. Both moves have advantages and disadvantages. It's a difficult choice.

☗12五歩 forces ☖12五居食い

☗1十横 is met with either ☖11六歩 or ☖3九角成. Gote in total spends 4 tempi to fully defend before his lion can leave.

☗11七歩 probably elicits ☖7四奔. This approach would take a long time for gote to cleanly defend. However, if gote threatens his winning chances by allowing the pawn trade with the spiteful ☖11六歩, he nets only a cost of half a tempo spent on the defense, the most time-effective option.

Is the a correct representation of the starting position of this study?

I am going through your posts, but still, my first thought was that Gote has a Queen and Lion and that should be a material advantage so devastating that I am surprised that there is something to play for for Sente.

A group of step movers proves quite impenetrable to a lone lion. It helps that gote's ranged pieces are strong, but numbers definitely matter in the endgame. Gote needs to promote enough pawns to make a useful hole for his lion after sente goes into defensive position and probably then still needs the help of 1-2 ranged pieces. Promoting the tiger will be a goal.

In fact, in the endgame: K+2S+2C+2FL+2BT vs K+Ln, the step movers are winning. It requires some complicated manoeuvres, and the simplest outline for a plan I came up with had 11 phases, including 3 sacrifices for tempi. The main idea is a wall of pieces crawling back and forth like a worm, running to the edge while stragglers from the back sacrifice themselves at key times to allow the most advanced pieces to gain another rank.

Four decent step movers are good enough to draw against a lion. Gote needs to trade tokins for step movers, resulting in the endgame (K+Ln+FK+FS vs K+SM+Kr+4 steppers). Thus, the attack needs to be properly timed and well-planned. It's not unlikely that gote would have to contend with a Kr+SM battery. I'm not fully convinced it's a win for gote.

Yes, the diagram is correct

A)☗11七歩☖11六歩☗同歩☖同獅☗12五歩☖12五•11五獅☗1十横☖10二角

B)☗11七歩☖7四奔☗1十横☖8四角☗12八豹

C)☗1十横☖11六獅☗12五歩☖12五•11四獅☗4十象☖10二角

D)☗1十横☖11六獅☗12五歩☖12五•11四獅☗12四反成☖12四•11三獅☗4十象☖8八角

Line C looks to be more accurate, after lots of consideration. I'm about 90% happy to move on from the position shown from diagram C. What do you guys think?

Yes I've gone through this now and think the same. 

By the way is this against buchi from 81dojo?

If I want to give good move suggestions I need to go through the possibilities tomorrow. But do I understand that the last move with the bishop was acceptance of the situation, that it is not possible to promote him quickly, therefore it is okay to exchange him against lance + reverse chariot. If so, my first suggestion would be to attack with the lion. Or at least with the free king, with the option to get the controll over the situation at 12th column later on.

But as said I need more time to give top three moves. 

Is there another buchi? The one who immediately goes for a boring structure, regardless what you do, and tries to take all the pawns. Plays very quickly. I was never made for speed. My strength goes down quite sharply as time controls get shorter. This game wasn't played at 81dojo, although I have played him there.

It was only necessary to promote the bishop if gote couldn't get both it and the free king to defend 12四 with sente's 12-pawn gone. It's not acceptable for the free king to leave its defense of 12四. Only the lion can leave. More importantly, it's sente to move.

9十一金: I think the lion is going to clean the pawn area around the leopard and might move on to the lance. Therefore I would try to do something at that place. The blind tiger doesn't do if he goes alone because of the one missing field in his front. 

1九横: I think it would be great to bring him to 7th rank. But on the downside this would be to slow to prevent gote from cleaning sentes left flank with the lion. So it may be to early to climb further than that.

5十一金: maybe, so you can move on with th copper at 4十一, and the whole king area pieces. But I don't consider this as good as the other moves. 

The golds have no reason to move from what will eventually be good places for them in the final stages of this endgame. 1九横 seems like a reasonable move to look at. I have highlighted 2 other moves.

5十銅: The bronze is spread a bit wide where it is currently serves no purpose. Maybe it can help create a wall in the future, so I prefer it join its friends.

10十豹: This seems a better alternate to delaying the lion's attack against the chariots, without having to commit. Note: Sente will just trade the chariots off for bishop and pawn if the lion gets imminently close, which is fine for both sides. This at least will make gote use 1 or 2 extra tempi later on, so it's not bad to just leave them alone. This move is also good if sente eventually decides the leopard should join an effort to build a wall. Its current position, far away from anything of worth, is terrible.

We can expect gote to respond to any move with 9六獅

I think it's time to look at more simplified endgames to figure out exactly what the goals should be. This is one where gote gets all the time he wants, with sente in a strong castle, as one would expect. If gote can win this, it's likely winnable.

My first idea would be 6七獅. 8八麒. 4八と. Maybe I can think later about it in more detail. 

6七獅 then 8八麒 is a blunder. 同奔 同横 同獅 and gote easily wins. Only reply to 6七獅 is 7九麒. Gote is in a position where even a 1-for-1 trade 奔 for 横 is ideal.

Sente cannot hold without his side mover. It cannot be lost for anything short of gote's lion.

I would still move 6七獅, then after 7九麒, I would move 4八と. After this I would try to go for the 横 with the 獅. If 横 moves upwards, I'll go 8八獅 for the 麒.