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41

It's quite a fun problem to think about, before getting to the calculation of long variations, try to first spot the key idea needed to crack the problem. Here are the first observations that come to my mind which eventually led me to spot the solution, let's break them down step by step: a) With our bishop eyeing g7 and our doubled pawn formation on g6-g7,...


38

You are right, this is nonsense. From the FIDE laws of chess, article 5: The game is drawn when the player to move has no legal move and his king is not in check. The game is said to end in ‘stalemate’. If capturing en passant is possible, it is a legal move so if it is the only option, Black is required to play the move. (Or not to move at all and lose ...


29

Stalemate is a draw in classical chess yet there are other chess variants both historical and modern where stalemate is not a draw. Very early versions of Chess, such as Shatranj Chess (props to Andrew Latham) declare the player causing stalemate the winner and even today there are callings to return to that rule. for example: Larry Kaufman Chess Life ...


22

As Totero notes, changing stalemate in this fashion would drastically change endgame play. Currently, one must learn how to recognize different King/Pawn endings, and how other pieces interact with these endings. Opposite- vs same-color Bishops, Knight/Pawn vs Knight, Rook/Pawn vs Rook, and other basic variations. Changing stalemate to a win would throw ...


17

Putting your king in check is not a legal move as you've realized. Of course, if Black has any OTHER legal moves he can and should play one of them! If a side TO MOVE does not have ANY legal moves, that would be a stalemate, not a checkmate (which is delivered only by the side making the check)


16

I think stalemate is a draw for the same reason that dropping the white ball when potting black is a loss in 8-ball pool - it gives the losing player a granule of hope until the very end, and it ensures that the winner must be clinical in securing his win. With regards to whether this flows logically from the other rules of the game - chess is, after all, a ...


16

Two conditions must apply for a position to be checkmate: The player to move has no legal moves. His king is in check. The first is true here, but the second isn't, so it's not checkmate. When a player to move has no legal moves but isn't in check, it's called stalemate, and it's an immediate draw.


15

Oh sure, here are two examples (annotated): This is a neat puzzle from the chess.com tactics, with white to play! [title "White to play!"] [fen "1q6/2b2ppb/4p1k1/7p/2Np1p1P/3P1Q2/6PK/8 w - - 0 1"] 1.Ne5+ Bxe5 {black has to take else white either checkmates or wins the queen.} 2.Qg3+ fxg3+ {Pawn takes queen is forced else white checkmates} 3.Kh3 {and ...


14

I'd use the term you already mentioned, "rambling rook", for this (at least when it's a rook). Tim Krabbé claims to have invented it: If the term 'Rambling Rook' sounds unfamiliar, this could be because I invented it. In Russian it is beshenaya ladya, in Dutch dolle toren, both meaning 'crazy rook.' There is no English term, and I thought a little ...


13

This is stalemate; you're right that Black can't move, but (unfortunately for you) in Chess this means it's a draw.


12

I think I found a double-self-smothered-stalemate that could occur via sequence of legal moves from the normal starting position. [FEN "5bnk/4ppbp/4P2p/5P1P/p1p5/P2p4/PBPP4/KNB5 w - - 0 1"] 1. c3 f6 Each player has seven pawns and two dark-square bishops, so one pawn from each player must have been promoted. Once White's b pawn has captured to a3 and ...


12

An exhaustive computer search shows that as expected K+N cannot in general force stalemate against a lone K. In fact, the defending King can avoid stalemate as long as it's not on one of the six-square triangular neighborhoods of the corners shown in the following diagram [Title "Danger Zone"] [fen "kkK2Kkk/kK4Kk/K6K/8/8/K6K/kK4Kk/kkK2Kkk w - - 0 0"] even ...


11

This would be checkmate, because the king is in check and has no valid move to escape. But it's impossible to get into this position if you follow normal chess rules. The most you can do is a double-check (using a discovered attack), but your position shows a triple-check. The stalemate rule is only applicable when the king is not in check, so it doesn't ...


11

Stalemate is defined as the player's whose turn it is to not be in check, & cannot make a legal move (black's only piece, the king, can only move to squares where it will be in check, which is illegal). By playing Rb6 (or possibly Rxb6), your friend walked into that exact situation. Essentially, she blocked off all the squares the King could move to, ...


10

If you mean he can't move his king anywhere because if he does his king will be in check, but none of your pieces are attacking him at the moment, and it's his turn, then yes, it's called a stalemate because he has nothing to play but his king isn't attacked by any one of your pieces, and this is a draw. P.S. that is if none of his pieces are able to move, ...


10

This is a proposed solution, I wonder if we can find more patterns like this with more pieces on the board


10

The FIDE Laws of Chess provide some guidance. Rule 6.2.1 says you must move the piece before hitting the clock: During the game each player, having made his move on the chessboard, shall stop his own clock and start his opponent’s clock (that is to say, he shall press his clock). This “completes” the move. According to rule 8.1.2, you must move the ...


10

Take your pick. Conventionally in computer chess, we express your idea of phases as "plies", or half-moves, where 2 plies is one "turn". You can detect checkmate in the ply where the checkmating move is made, but it is more common for checkmate to be detected in the following ply, where your program generates legal moves for the mated player, only to find ...


10

Right now Black can only move his/her pawns. There are 1+4 moves left. To win, White needs the black king to capture the g7 pawn but not the g6 pawn. Therefore, the King must protect it (probably from f5). Let's try to get the king there: 1. Kb3 a4+ 2. Kc4 a3 3. Kd5 a1Q 4. Bxa1 a2 5. Ke5 (conveniently blocking the long diagonal) Kxg7 6. Kf5+ Now 6... Kg8 ...


9

I remember reading somewhere once which advocated that stalemate should be (could be) 3/4 point. Unfortunately, a quick google search turned up nothing. The idea is interesting. It seems that you gained more by stalemating your opponent than you gain if the position is completely equal. By similar logic, the stalemated side seems to have not lost as badly ...


9

Here's a simpler mutual smothered stalemate (9 men on a side, no promoted pieces): [Title "Mutual smothered stalemate"] [fen "5brk/4p1pb/4P1p1/6P1/1p6/1P1p4/BP1P4/KRB5 w - - 0 1"]


9

When it is your opponent's turn to move and none of your opponent's pieces can move other than his king, and if the king moves or captures your piece, it will be under check, then this type of position is called as stalemate and the result will be a draw. Few Examples: Simple one with just 3 pieces on Board (Black To Move): Here, Black king has nowhere ...


8

If you were dominating so much, you should have checkmated him. It's not the fault of the game that your mistakes may mean you don't win. The appeal of chess comes partly from the fact that it is hard. One of the reasons for that is that there is quite a large drawing margin -- you may have a great position at some point, but there may still be many ways to ...


8

Reduce number of units from Noam's record of 18 to a new record of 15. (8+7 units, no promoted units necessarily on the board, pawn captures all achievable): [Title "Minimal mutual smothered stalemate"] [fen "5brk/4p1pb/4P1p1/6P1/6PB/6PK/6PP/8 w - - 0 1"] Is this the best possible? It's interesting that this solution is asymmetric. If you wrap both kings ...


8

There would definitely be some logic in considering Stalemate a win (after all, the opponent's King has to move and and will be captured on next move, so that should be a win). However, this would have a huge impact on the whole Chess game. The reason is that, if Stalemate wins, now all King+pawn VS King endings are winning. Thus being one pawn ahead, ...


8

Simple reason - you cannot kill the king in his current place and the king is dead if he moves. So they maintain status quo till eternity, meaning stalemate.


8

It's possible to build a bit on magd's answer. Consider the following position. [Title "White to move"] [SetUp "1"] [FEN "8/8/8/8/8/1N6/pk1K4/8 w - - 0 1"] 1. Na1! Kxa1 2. Kc1 The only way to draw is 1. Na1! Kxa1 2.Kc1 (or 2. Kc2) stalemate. I think there are some nice studies with this theme, but I can't find them right now.


7

This is a bug. The GamePigeon app was written by non-chess programmers, their focus is not on chess. They're not specalized in chess apps, chess is just one of the many things they do.


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