What is the most number of consecutive captures that you can have on the same square in a standard game of chess? Assume that black and white alternate in taking turns. Good luck!
Since we are talking about a standard game of chess (although with both players co-operating), we know that there are four pieces that cannot possibly make a capture in the series:
- the two bishops on the wrong coloured squares
- one of the kings (the other can be the last to capture)
- the first piece that gets captured (cannot be any of the above).
Furthermore, getting the maximum number of pawns involved is tricky. It seems best to group the pawns in quadruplets (e.g. all four pawns on A and B files), and then sacrifice 1 pawn to promote the other 3. We can also feed the useless bishops from above to the lane-switching process, each sacrificed bishop allows 1 pawn pair to promote.
Since we can leave two pairs of pawns unpromoted and attacking the same square, and the useless bishops enable 2 more pawn pairs to promote, we will only have to sacrifice 2 pawns to promote the rest of them.
Therefore, the maximum number of consecutive captures on the same square is
26. (32 initial pieces minus the 2 bishops, the two unavoidably sacrificed pawns, a king, and the piece that was the first to be captured)
To confirm that this is possible, let's construct an actual game.
To get started, let's make the unavoidable sacrifices. The plan is to do the captures at f5.
1. b4 a5 2. bxa5 c5 3. d4 cxd4 4. g4 g6 5. Bf4 f5 6. Bg3 f4 7. h4 fxg3 8. h5 Bg7 9. h6 e6 10. hxg7 g2 11. e4
In this position we can confirm that now every piece can eventually reach f5 without any further captures, so it's just a matter of doing the tedious arrangement work: (this could definitely be improved, in efficiency and coherence both)
11. - Bb7 12. Rh5 g2 13. Rg5 h5 14. c4 h4 15. c5 h3 16. Nf3 h2 17. Nc3 d3 18. c6 h1=N 19. Nh4 Ng3 20. Kd2 g1=N 21. Ke3 b4 22. f4 b3 23. f5 b2 24. Kf4 Nf3 25. Bh3 d2 26. Qc2 Qf6 27. Nd5 Rh5 28. Ne3 d5 29. c7 d4 30. c8=R+ Kd7 31. Qc5 b1=R 32. Qe5 Rb5 33. Rc5 Ra6 34. a4 Rd6 35. a6 Rd5 36. a7 Nh6 37. g8=B d1=B 38. Bh7 Bc2 39. a8=N Bc8 40. Nc7 Nc6 41. Ne8 Ne7 42. Ng7 d3 43. a5 Nd4 44. a6 d2 45. a7 d1=Q 46. a8=N Qd3 47. Nc7 Kd8 48. Nce8 Bd7 49. Nd6 Qf8 50. Ra5
Now all the ducks are properly lined up:
50. - Qxf5+ 51. Qxf5 gxf5 52. exf5 Qxf5+ 53. gxf5 Bxf5 54. B3xf5 exf5 55. Rxf5 Rdxf5+ 56. Nhxf5 Ngxf5 57. Rxf5 Bxf5 58. Ngxf5 Rbxf5+ 59. Rxf5 Nhxf5 60. Ndxf5 Nexf5 61. Bxf5 Nxf5 62. Nxf5 Rxf5+ 63. Kxf5
As a final note, it's worth noticing that doing black's last capture with a rook is important: trying to do it with a bishop or a knight comes with a nasty surprise: the white King won't be able to complete the final capture, because
the position would suddenly be a draw caused by the "insufficient material for checkmate" rule.
Found via Google search: https://timkr.home.xs4all.nl/records/recordstxt.htm#Longest%20capturing%20series
Note: This is from an actual game, and as such is not likely to be the longest possible.
Longest consecutive series of captures on one square: 12
Weiss - Burschowsky, Austria 1995
37.hxg4 hxg4 38.fxg4 Nhxg4 39.Nhxg4 Nxg4 40.Nxg4 Bxg4 41.Bxg4 Qxg4 42.Qxg4 Rxg4 and 8 moves later, White resigned.
@Bass comprehensively beat me to it but my solution is significantly shorter, so I'd hate to let it go to waste... Number of captures is the same.
1. d4 e6 2. d5 Be7 3. d6 g5 4. e4 g4 5. c4 g3 6. b4 gxh2 7. g4 f6 8. g5 c6 9. g6 h5 10. Bg5 fxg5 11. b5 h4 12. b6 h3 13. bxa7 b5 14. a4 b4 15. a5 b3 16. a6 b2 17. Ra5 g4 18. Rc5 Qa5+ 19. Nc3 b1=B 20. dxe7 d5 21. f4 Kd7 22. f5 Ba2 23. f6 Kd6 24. e8=B Ne7 25. f7 Nd7 26. f8=N Nf6 27. Bf7 Rh5 28. Nd7 Rb8 29. g7 Rb5 30. Nb6 Bb7 31. a8=N Re5 32. Ne2 g3 33. Nf4 g2 34. Nc7 g1=N 35. a7 Nf3+ 36. Kf2 Ne1 37. Rg1 h1=B 38. Qh5 Bf3 39. Rg5 h2 40. g8=B h1=B 41. a8=B Nc2 42. Bg2 Ne3 43. exd5 exd5 44. cxd5 cxd5 45. Rxd5+ Rexd5 46. Rxd5+ Bfxd5 47. Bgxd5 Bbxd5 48. Baxd5 Baxd5 49. Bxd5 Bxd5 50. Bxd5 Rxd5 51. N3xd5 N3xd5 52. Nfxd5 Nfxd5 53. Nbxd5 Nxd5 54. Nxd5 Qxd5 55. Qxd5+ Kxd5 *
Not really sophisticated, but (with promoted pieces) it's possible to do
27 consecutive captures on d5
in the following position:
The sequence of moves can be replayed here.