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Two Chances to Prove that You are Actually Smarter than Stockfish!

ChessAnalysisEndgame
Pawn with the Wrong Bishop Ending

A well known phenomenon in the ending is that if a player is left with just a king, bishop and rook pawn against a lone king, it can often be a forced draw if the bishop is of the opposite colour to the rook pawn's queening square and the player with the lone king can get to that queening square. For example, if this is the position:

https://lichess.org/study/YilAcjro/osd7l2S2

Black will draw this position with either colour to move. The black king can oscillate side to side by playing ...Ka8-b8-a8 and ensure a draw, as White has what is called the "wrong bishop" i.e. one on the different colour to his pawn's queening square. White can't do anything forcing without allowing a stalemate e.g. by playing 1. a7. If the white bishop were on a white square, White would instead be able to check the king and then promote the pawn and win.

A nice example of the phenomenon is the following puzzle, in which you have a chance to show that you are smarter than the Stockfish engine!!! How can White force a draw in 3 moves?

https://lichess.org/study/YilAcjro/3MYHGwlq

It's interesting to see the Stockfish engine struggle to properly evaluate this ending, at least on my computer. It does spot the correct 3-move continuation but misevaluates the position at the end of those 3 moves as -1.7, rather than completely drawn i.e. +0.0. The answer to the puzzle is:

https://lichess.org/study/YilAcjro/Y1kG0W1k

When White will draw after 3...gxh6 by just keeping his king near the h1-square and preventing either h-pawn from queening; or if Black refuses to take the bishop, then White will just play 4. Bxg7+ and still draw.

However, while the Stockfish engine might not be certain that the position after 3. Bh6!! is a draw, the tablebase sure is and confirms that 3. Bh6!! is the only drawing move in that position.

Don't worry if you didn't solve the puzzle and didn't prove that you were smarter than Stockfish. I'll give you one more chance to conclusively show that you are smarter than the engine.

But first let's just look at one quick game example to solidify our skill at this ending.

https://lichess.org/study/mFl5CEz0/oBLgdX1b

This is from a game Patrick McCartney (2031) - Michael Kliber (1995). Black is winning and had several moves he could have played here to keep the win in hand, though perhaps the deftest is 1...Bd1! 2. Ne1 g5 -++, as I've given above, and Black can eventually push the g-pawn down the board with care to ensure the victory.

However, the game continued:

https://lichess.org/study/mFl5CEz0/Gve2fLur

and the game was drawn 9 moves later as the white king can hang around the a1-square.

This time you have a second opportunity to prove you are smarter than Stockfish and you don't even have to find any moves!!! Do you think White is winning or that it's a draw?

https://lichess.org/study/YilAcjro/Tkbq3Qt1

I made it Black's move but it doesn't matter whose move it is. White can't kick the black king away from defending the queening square so it's a draw. If you worked out that it's a draw, guess what? You are undeniably smarter than Stockfish! My Stockfish assesses the position as +4.1, even though it is a draw with best play, as the black king just hangs around the h8-square. In fact, if you understand that the position is a draw and want to demonstrate to Stockfish how severely its endgame knowledge is inferior to yours, you can play out some moves against it in this position but I doubt it will learn as well as you have and will keep insisting that White is winning.

I'll give one final position to demonstrate that sometimes, bizarrely, the player with the pawn and wrong bishop can win, if the losing king is somehow prevented from getting to the queening square. This was a game I played with my blindfold account [you can try blindfold chess by going to Preferences > Blindfold chess (invisible pieces) and maybe even can join my blindfold team at
https://lichess.org/team/blindfold-simuls ]:

https://lichess.org/NB9qfN4T#82

After 41 moves had been played in this game, White could easily have drawn with a move like 42. Kf3 and then just hung around the h1-square with his king, since Black has what is called the "wrong bishop" as it is not the same colour as the black pawn's queening square, h1. But White played the only losing move in the position, 42. Kh5?? and after 42...Kf5, amazingly, he can't get back his king back to h1 and I went on to win.