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Shortest stalemate in serious tournament game

Yes, there has been a stalemate in a serious game that is under 30 moves long. According to Tim Krabbe's "Chess Records," the fastest such game happened in 27 moves. [Title "Sibilio-...
• 17.7k
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What is the fastest way to reach stalemate?

Sam Loyd, a famous puzzle composer, created this 10 move, 19 ply, stalemate game over 100 years ago. I found it via Google, in this post by AndersElborg on chess.com. Most black pieces are blocked, ...
• 24.9k

Longest sequence of mutually forced moves

Assuming you allow promoted material (since you didn't say anything :-), this (on Page 13 of the PDF) is the (unfortunately, extremely unknown) finite record since ages. It shows the record for the ...
• 16.8k

What is the highest number of different mates in 1 you can have in one (legal) position?

[FEN "1B1Q1Q2/2R5/pQ4QN/RB2k3/1Q5Q/N4Q2/K2Q4/6Q1 w - - 0 1 "] 105 mates — Nenad Petrovic, Sahovski Vjesnika 1947 (Chess Problem Database) In this position any check is mate. There are 3 knight mates ...
• 3,872
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What's the maximum amount of material that a puzzle with unique solution can have?

This must be the maximum for an illegal position (adapted from David's attempt): [Title "_David_, v. NDE: White to move and win"] [FEN "qqqqqqqq/qkqQqqqq/qqqQqqqq/qQQQqqqq/qqqqQqqq/...
• 8,104
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What is the longest known sequence of forced moves leading to a checkmate for one side?

If you don't mind a bushel of promoted Queens, you can get 14 half-moves . . . [Title "14 forced half-moves to checkmate"] [Fen "3b3k/qqqqq3/rr4NK/7R/5N1Q/7Q/B6Q/7R b - - 0 0"] 1... Rxg6+ 2. Nxg6+ ...
• 8,104

What is the highest number of different mates in 1 you can have in one (legal) position?

Anthony Stewart Mackay Dickens found another solution, also with 105 mating moves, but with only 17 units in the diagram (16 white and the black king): [title "Anthony Stewart Mackay Dickens, The ...
• 6,495
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From the start of the game what is the longest possible series of consecutive white moves where white can do those moves no matter what black does?

Three moves. On move 3, Black can crash through with his queen on f2 or d2 via several different squares, forcing White to respond. There is no series of White moves that can prevent all such checks. ...
• 19.8k

Youngest Player to beat a reigning World Champion?

I have not identified the record with certainty, but here are some young winners of World Champions in classical chess: N.Abdusattorov, 18y 4m 1d, vs Carlsen in Wijk aan Zee 2023 Rameshbabu ...
• 16.5k
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Problems: record for most mates-in-2

Sir Jeremy Morse, in Chess Problems: Tasks and Records, Introduction, cites this construction by E. Luukonen: [Title "E. Luukonen, Uusi Suomi, 1936"] [fen "kr6/pnPPPPPPPP/P2N4/R7/3BBN2/1Q6/3K3P/6R1 w ...
• 6,495

What is the fastest loss by a GM in a FIDE classical game?

I also did some research and found this game IM Hagen Poetsch vs GM Yair Kraidman in Vienna Open 2013 where black resigned in 4 moves. Black has forgotten that white recaptured with the Queen not the ...
• 2,768

What is the highest number of pieces from one side that can be involved in a checkmate?

Here is a solution with all 16 white pieces, all mandatory for checkmate, without promoted units and without needing to protect the white king from checks. If you remove any white piece but the king, ...
• 16.5k
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What is the maximum number of passed pawns in a position?

EDIT: record is now 20.0 moves! (See below.) If we like pawns undoubled... [title "16 non-doubled passed pawns in 21.0 moves"] [fen ""] [startply "42"] 1. g4 h5 2. g5 Rh6 3. gxh6 g5 4. h4 g4 5. b4 ...
• 13.3k

Fastest possible checkmate by en passant

According to this page the shortest known mate by en passant capture is in 5.5 moves (that is, White mates on move 6), and was published by Benko in Chess Live & Review in 1976: [Title "Pal Benko'...
• 8,104
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List of female chess players by peak FIDE rating

The raw data which could be used to extract this information is available on the FIDE website (from 2001) and the Olimpbase website (before 2001). What you will need to do is clean the data (the older ...
• 99.6k
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How many times can the same pawn move be made in a game?

Eight is the maximum due to the geometry of the board. Only five of one side and three of the other can converge on the same single square. Addendum: o@Red_Floyd2 on reddit found a faster way in 18.0 ...
• 17.7k
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Maximum number of pieces on board in dead position

EDIT 30-Dec-2023: added the R(1,D) position with 32 units. So Challenge 1 is now completely resolved. Apologies that the first few lines are a bit theoretical. I reach the actual chess as soon as I ...
• 13.3k
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Fastest possible checkmate by en passant

The same question has also been discussed and answered in the lichess forum, and as mentioned by others already, the answer is 11 half-moves for white and 12 half-moves for black. You might find some ...
• 2,456
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Fastest King vs King endgame

This is a famous task, originally tackled by Sam Loyd and only improved a century later. See http://www.chessvariants.com/problems.dir/twokingstask.html, which gives the refinement by Ponzetto: [FEN ...
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What is the longest proven forced win (including 50 & 75 move rules)?

Otto Blathy is famous for his long mate problems. There are different records depending on whether you allow an illegal starting position, or promoted pieces, or minor duals in the solution, so your ...
• 16.5k
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Longest *shortest available* fixed sequence of moves leading to checkmate?

In other words, you wish for the record length for a completely dual-free sequence. Every White move must be absolutely unique to any possible by Black. Shorter, dualed mating sequences do not count. ...
• 17.7k
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Is this the quickest way to clearing the board to two kings?

Samuel Loyd found faster in 1895. [FEN ""] 1. c4 d5 2. cxd5 Qxd5 3. Qc2 Qxg2 4. Qxc7 Qxg1 5. Qxb7 Qxh2 6. Qxb8 Qe5 7. Qxc8+ Rxc8 8. Rxh7 Qxb2 9. Rxh8 Qxa2 10. Rxg8 Qxd2+ 11. Kxd2 Rxc1 12. Rxg7 Rxb1 ...
• 5,040
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Longest possible FEN

The FEN consists of six parts (see definition of FEN here): piece placement: at most 64 characters, one for each square plus 7 times "/" to delimit ranks = 71 characters active color: one character ("...
• 20.9k

Can there be a checkmate with maximum points of material (103) while covering 64 squares?

As per Hauke's invitation, here is an optimal proof game for such a position. This is optimal because a queen must move to give the Black king a square and forty pawns moves must take place. White's h ...
• 17.7k

The 50 moves game

I have managed 106 single moves (see below). As OP notes, if 12 pawns promote, capturing the other 4 pawns, then all captures by officers must be on 1st/8th ranks. So that would be 88+26=114. Can this ...
• 13.3k

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/...
• 4,216
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Shortest sequence of moves to create biggest material imbalance

I got this, which is much shorter. [FEN ""] 1. a4 a5 2. b4 b5 3. c4 c5 4. d4 d5 5. e4 e5 6. f4 f5 7. g4 g5 8. h4 h5 9. bxa5 Bd6 10. axb5 Be6 11. dxc5 Nf6 12. cxd5 O-O 13. fxe5 Rf7 14. exf5 ...
• 558
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What is the farthest away a game can be from a guaranteed checkmate?

The position with the longest known sequence away from checkmate has a mate in 595 moves. It is a computer-verified extension of the 8-piece table record found by Lutz Neweklowsky. By "verified,&...
• 17.7k