25 votes
Accepted

What is sufficient mating material?

Most basic first - this rule is the reason that King vs King is an immediate draw. Neither side has a piece to check with, let alone checkmate with. A position that is a draw because neither side can ...
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  • 25.8k
14 votes
Accepted

What will happen if you have a position where no one can lose?

I was wondering the outcome for a standard format chess game will it be draw because no one can win. According to the FIDE Laws of Chess: 5.2.2 The game is drawn when a position has arisen in which ...
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  • 74k
14 votes

What happens after two kings stay on the board?

This is covered in FIDE's Laws of Chess 5.2b) The game is drawn when a position has arisen in which neither player can checkmate the opponent’s king with any series of legal moves. The game is said ...
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  • 497
11 votes
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Maximum number of pieces on board in dead position

Funny task. I think I'm still pretty far from the maximum, but here is a suggestion with 23 men: [Event "?"] [title "Challenge 3, 23 units"] [FEN "NRN1k1bn/QRKpPp2/PPpP1Pp1/2P3Pp/7P/8/7B/8 w - - 0 ...
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  • 12.8k
11 votes

Maximum number of pieces on board in dead position

I've come up with 23, in the following position, with promotions: [Event "?"] [Site "?"] [Date "????.??.??"] [Round "?"] [White "?"] [Black "?"] [Result "*"] [FEN "nb2k3/2p5/1pP5/1Pp5/2P1p1p1/3pPpPp/...
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  • 3,924
10 votes

Is the dead position problem solvable?

Computer detection of dead positions is much trickier than people think. It is unlikely that an algorithm exists that runs in reasonable time and is 100% accurate. It is easy to check for a simple ...
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  • 4,830
10 votes
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What happens if me and my opponent only have kings?

Since you can't move your king into check, you can't legally check the other king. The Laws of Chess, section 5.2b, states that: The game is drawn when a position has arisen in which neither ...
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  • 216
10 votes
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Why does this game not end as a draw by insufficient material?

Why this game does not end immediately as a draw by insufficient material? Two reasons. There is no rule regarding ‘insufficient material’. What there is is a draw due to a ‘dead position’. This is ...
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  • 74k
9 votes
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A special "dead" position

I am not sure if this is exactly what you are asking for, but here is a try. [FEN "8/8/8/2p1p1p1/2P1PkP1/4Q1RB/3PPpPp/3n1Kbr b - - 0 1"] [startflipped ""] 1... Nxe3+ 2.dxe3+ {2....
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  • 12.8k
8 votes
Accepted

Longest "death certificate"

Here is such a position. [FEN "1k6/p1p1p1p1/P1P1P1P1/8/8/8/PKP1P1P1/8 b - - 0 1"] [startlfipped ""] With Black to move, no side can make any progress. White still has plenty of ...
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7 votes

What happens after two kings stay on the board?

It is a draw (tie) because of "insufficient mating material". The game ends in this state. The condition also arises when both sides are down to King+Bishop or King+Knight with no pawns on the board.
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7 votes

What is sufficient mating material?

The quote The game is draw when a position is reached from which a checkmate cannot occur by any possible series of legal moves Is a good summary in itself. It is not just how much material e.g. ...
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  • 6,524
7 votes

Maximum number of pieces on board in dead position

The three dead position challenges are (1) general (2) no finite mandatory stalemate (3) definitely no stalemate possible ever. (3)=>(2)=>(1). Retro enthusiasts often sub-divide Task Records into 3 ...
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  • 9,378
6 votes

How long can a player hold off a draw by the 50-move rule?

The answer is trivially the starting position - [fen ""] This exact question hasn't been asked before (I think) but it has been answered here. Here is the relevant part of that answer - ...
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  • 74k
6 votes

Automatic draw rules

Yes, since it is not possible to produce a checkmate in these circumstances. See also the FIDE rules: 1.3 If the position is such that neither player can possibly checkmate the opponent’s king, the ...
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  • 3,622
5 votes

What is sufficient mating material?

One interesting forced mate which nobody has mentioned is K+N+N v K+P. Provided the pawn is not far advanced the side with the 2 knights drives the opposing king towards a corner. At a certain point ...
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  • 74k
4 votes

Why does this game not end as a draw by insufficient material?

A bit late, but Miguel Ambrona recently developed an algorithm to assess whether a given position is a draw, or loss on timeout, under FIDE rules—in short, whether a checkmate is at all possible. ...
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4 votes
Accepted

How long can a player hold off a draw by the 50-move rule?

I interpret the following White will play as long as possible, and not want to lose. Black will claim a draw as soon as possible, if not win as meaning that Black does not help (i.e., Black tries to ...
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  • 849
3 votes

A question about draw detection in chess engines

I actually did the experiment and will answer now. Three main factors go into the evaluation (as king safety doesn't play the slightest role): material, space, and movability. The effect of space is ...
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3 votes

What happens if me and my opponent only have kings?

When you only have Kings then you can take a tour of the entire board till the end of the World without any hesitation . :-) (Just Joking ) . The Game at this point is a DRAW . Since neither Player ...
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3 votes

A position in which there is no possible checkmate

I think that is limited to just a few positions. A lone king vs. king. king and bishop vs. king. A king and bishop vs. king and same colored bishop as the other side. A king and multiple bishops of ...
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  • 31.9k
3 votes

What is sufficient mating material?

K+N+B, K+B+B, K+R, K+Q, and K+N+N are. The latter is a helpmate. K+N and K+B are insufficient.
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  • 19.8k
2 votes

What is sufficient mating material?

AFAIK sufficient mating material is considered as such if a "helpmate" can be demonstrated in any number of moves. Put another way, it is as if the player that ran out of time is out of the game, and ...
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  • 121
2 votes

Is the dead position problem solvable?

I would expect that it is a good bit easier to write a program that is good at detecting dead positions than to write a program that plays chess well. A simple strategy may be to play out a large ...
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2 votes

A special "dead" position

Example showing why the checking condition is needed to make this an interesting puzzle: [FEN "k7/Pp4p1/1P6/8/8/6p1/1P4Pp/7K w KQkq - 0 1"] Whoever moves, the game soon ends in stalemate, ...
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2 votes

A special "dead" position

Since Evergalo asked, I also post a solution, where neither side is in check at the start. Problem chess etiquette says that everything that the composer does not rule out explicitly isn't cheating - ...
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2 votes

Automatic draw rules

Yes, in these two cases there is insufficient mating material and the game will always end in a draw.
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1 vote

A special "dead" position

I think I have found a position meeting all the requirements, where White, on move, is not in check. Moreover, White can play a non-checking move. Legal position, 13 units, no promoted pieces. White: ...
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  • 12.8k
1 vote

Is the dead position problem solvable?

I think the answer is probably not. In fact I would say that the introduction of the dead position rule to replace the previous draw by insufficient material was a mistake. (Btw why did FIDE excise ...
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1 vote
Accepted

Automatic draw rules

It would be absolutely reasonable, because there is only one way to end such positions, draw. There are other positions like these as well. And for this, there is a rule called dead position rule in ...
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  • 4,322

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