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Classic game replay

H. Kloos vs Adolf Anderssen, 1861

This replay preserves the complete 38-ply score of Anderssen playing Black across 19 numbered moves. The board can be advanced one ply at a time; the notes stick to observable board changes rather than guessing at the players’ intentions.

On this page
  1. Practice positions
  2. Replay with move-by-move board facts
  3. PGN
  4. Sources and checking
  5. Continue with another game
White
H. Kloos
Black
Adolf Anderssen
Event
Amsterdam
Year
1861
Result
0-1
Opening
C50 Italian Game: Giuoco Pianissimo, Italian Four Knights Variation

Opening reference: Italian Game: Giuoco Pianissimo, Italian Four Knights Variation (C50).

In this game, 20 half-moves are labelled opening, 18 middlegame and 0 endgame. The score contains 10 captures and 7 checks or mates; before a recorded move, the position offered a median of 37 legal choices. The final recorded move is 19...Bxf2#, which is checkmate; the stored result is 0-1.

Practice positions

The daily trainer uses a short set of positions from this complete score. Each link goes to the exact half-move rather than only the numbered move.

  1. 9...g4 — Create pressure on f39...g4 was a leading choice in the fixed engine check.
  2. 14...Qh4+ — A forcing check14...Qh4+ was a leading choice in the fixed engine check.
  3. 19...Bxf2# — Checkmate19...Bxf2# was a leading choice in the fixed engine check.

Replay with move-by-move board facts

The board, fact panel and transcript use the same legal score. “Fixed engine check” means Stockfish 17.1, one thread, a fixed 25,000-node search and 3 candidate lines. It compares moves under one reproducible setting; it does not claim to reconstruct a player’s thoughts.

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H. Kloos vs Adolf Anderssen, 1861

Start position

Use Previous and Next on the board, or select a move in the transcript. The board fact and fixed engine check remain visible until you choose another move.

Opening · 1.e4 to 10...Bxg4

  1. 1.e4 Claim central space

    Board fact: White moves the pawn from e2 to e4; from there it controls d5 and f5.

    Fixed engine check: Ranked first · e4 e5 Nf3 Nc6.

  2. 1...e5 Claim central space

    Board fact: Black moves the pawn from e7 to e5; from there it controls d4 and f4.

    Fixed engine check: Ranked first · e5 Nf3 Nc6 d4.

  3. 2.Bc4 Develop the bishop

    Board fact: White develops the bishop from f1 to c4; from c4 it attacks Black's pawn on f7.

    Fixed engine check: Near the leading choice · Bc4 Nf6.

  4. 2...Nf6 Develop the knight

    Board fact: Black develops the knight from g8 to f6; from f6 it attacks White's pawn on e4.

    Fixed engine check: Ranked first · Nf6 Nc3 Bc5 Nf3.

  5. 3.Nc3 Develop the knight

    Board fact: White develops the knight from b1 to c3; from there it controls d5 and e4.

    Fixed engine check: Ranked first · Nc3 Bc5.

  6. 3...Bc5 Develop the bishop

    Board fact: Black develops the bishop from f8 to c5; from c5 it attacks White's pawn on f2.

    Fixed engine check: Ranked first · Bc5.

  7. 4.Nf3 Develop the knight

    Board fact: White develops the knight from g1 to f3; from f3 it attacks Black's pawn on e5.

    Fixed engine check: Ranked first · Nf3 Nc6 d3 d6.

  8. 4...Nc6 Develop the knight

    Board fact: Black develops the knight from b8 to c6; from there it controls d4 and e5.

    Fixed engine check: Ranked first · Nc6 d3 O-O Bg5.

  9. 5.d3 Advance the d-pawn

    Board fact: White moves the pawn from d2 to d3; from there it controls e4 and c4.

    Fixed engine check: Ranked first · d3 a6 O-O d6.

  10. 5...d6 Advance the d-pawn

    Board fact: Black moves the pawn from d7 to d6; from there it controls e5 and c5.

    Fixed engine check: Ranked first · d6 Na4.

  11. 6.h3 Advance the h-pawn

    Board fact: White moves the pawn from h2 to h3.

    Fixed engine check: Ranked first · h3.

  12. 6...h6 Advance the h-pawn

    Board fact: Black moves the pawn from h7 to h6.

    Fixed engine check: Ranked first · h6.

  13. 7.a3 Advance the a-pawn

    Board fact: White moves the pawn from a2 to a3.

    Fixed engine check: Ranked first · a3 a5 Be3 O-O.

  14. 7...Bb6 Create pressure on f2

    Board fact: Black moves the bishop from c5 to b6; from b6 it attacks White's pawn on f2.

    Fixed engine check: Ranked first · Bb6.

  15. 8.O-O Kingside castling

    Board fact: White castles kingside, moving the king to g1 and the rook to f1. The move changes king safety and develops the rook in one turn.

    Fixed engine check: Ranked first · O-O Be6.

  16. 8...g5 Advance the g-pawn

    Board fact: Black moves the pawn from g7 to g5; from there it controls f4.

    Fixed engine check: Ranked first · g5.

  17. 9.Be3 Develop the bishop

    Board fact: White develops the bishop from c1 to e3; from e3 it attacks Black's bishop on b6 and Black's pawn on g5.

    Fixed engine check: Near the leading choice · Be3 g4.

  18. 9...g4 Create pressure on f3

    Board fact: Black moves the pawn from g5 to g4; from g4 it attacks White's knight on f3 and White's pawn on h3.

    Fixed engine check: Ranked first · g4 Nh2 gxh3 g3.

  19. 10.hxg4 Exchange on g4

    Board fact: White's pawn takes the pawn on g4; the move changes the central pawn contact; White accepts doubled pawns on the g-file; white is ahead by 1 conventional material point after the capture.

    Fixed engine check: Ranked first · hxg4 Bxg4 Bxb6 axb6.

  20. 10...Bxg4 Recapture on g4

    Board fact: Black's bishop recaptures the pawn on g4; from g4 it attacks White's knight on f3; material is level after the capture.

    Fixed engine check: Ranked first · Bxg4 Nd5 Rg8 Bb5.

Middlegame · 11.Ne2 to 19...Bxf2#

  1. 11.Ne2 Reroute the knight

    Board fact: White moves the knight from c3 to e2; from there it controls d4, c3 and f4.

    Fixed engine check: Recorded move; Bb5 ranked higher · Ne2 Bxf3 gxf3 Rg8+.

  2. 11...Bxf3 Exchange on f3

    Board fact: Black's bishop takes the knight on f3; from f3 it attacks White's knight on e2 and White's pawn on e4; black is ahead by 3 conventional material points after the capture.

    Fixed engine check: Ranked first · Bxf3 gxf3 Rg8+ Kh2.

  3. 12.gxf3 Recapture on f3

    Board fact: White's pawn recaptures the bishop on f3; the move changes the central pawn contact; White accepts doubled pawns on the f-file; from f3 it reinforces the pawn on e4; material is level after the capture.

    Fixed engine check: Ranked first · gxf3 Rg8+ Kh2 Nxe4.

  4. 12...Rg8+ A forcing check

    Board fact: Black moves the rook from h8 to g8; the move checks White's king; the rook now occupies the open g-file; from g8 it reinforces the king on e8.

    Fixed engine check: Ranked first · Rg8+ Kh2 Nxe4 Kh3.

  5. 13.Kh1 Answering the check

    Board fact: White answers the check by moving the king from g1 to h1.

    Fixed engine check: Recorded move; Kh2 ranked higher · Kh1 Nxe4 Bxf7+ Kxf7.

  6. 13...Nxe4 Exchange on e4

    Board fact: Black's knight takes the pawn on e4; from e4 it attacks White's pawn on f2; black is ahead by 1 conventional material point after the capture.

    Fixed engine check: Playable; Nd5 ranked higher · Nxe4 Bxf7+ Kxf7 Ng3.

  7. 14.Ng3 Create pressure on e4

    Board fact: White moves the knight from e2 to g3; from g3 it attacks Black's knight on e4.

    Fixed engine check: Ranked first · Ng3 Qh4+ Kg2 Rxg3+.

  8. 14...Qh4+ A forcing check

    Board fact: Black moves the queen from d8 to h4; the move checks White's king; from h4 it attacks White's knight on g3.

    Fixed engine check: Ranked first · Qh4+ Kg2 Rxg3+ fxg3.

  9. 15.Kg2 Answering the check

    Board fact: White answers the check by moving the king from h1 to g2; from there it controls f3.

    Fixed engine check: Ranked first · Kg2 Rxg3+ fxg3 Qxg3+.

  10. 15...Rxg3+ Capture with check on g3

    Board fact: Black's rook takes the knight on g3; the move checks White's king; the rook now occupies the open g-file; from g3 it attacks White's pawn on f3; black is ahead by 4 conventional material points after the capture.

    Fixed engine check: Ranked first · Rxg3+ fxg3 Qxg3+ Kh1.

  11. 16.fxg3 Recapture on g3

    Board fact: White's pawn recaptures the rook on g3; the move changes the central pawn contact; from g3 it attacks Black's queen on h4; white is ahead by 1 conventional material point after the capture.

    Fixed engine check: Ranked first · fxg3 Qxg3+ Kh1 Qh3+.

  12. 16...Qxg3+ Recapture on g3

    Board fact: Black's queen recaptures the pawn on g3; the move checks White's king; from g3 it attacks White's pawn on f3; material is level after the capture.

    Fixed engine check: Ranked first · Qxg3+ Kh1 Qh3+ Kg1.

  13. 17.Kh1 Answering the check

    Board fact: White answers the check by moving the king from g2 to h1.

    Fixed engine check: Ranked first · Kh1 Qh3+ Kg1 Bxe3+.

  14. 17...Qh3+ A forcing check

    Board fact: Black moves the queen from g3 to h3; the move checks White's king; from h3 it attacks White's rook on f1 and White's pawn on f3.

    Fixed engine check: Ranked first · Qh3+ Kg1 Bxe3+ Rf2.

  15. 18.Kg1 Answering the check

    Board fact: White answers the check by moving the king from h1 to g1; from g1 it reinforces the rook on f1.

    Fixed engine check: Ranked first · Kg1 Bxe3+ Rf2 Bxf2#.

  16. 18...Bxe3+ Capture with check on e3

    Board fact: Black's bishop takes the bishop on e3; the move checks White's king; from e3 it reinforces the pawn on a7; black is ahead by 3 conventional material points after the capture.

    Fixed engine check: Ranked first · Bxe3+ Rf2 Bxf2#.

  17. 19.Rf2 Answering the check

    Board fact: White answers the check by moving the rook from f1 to f2; from there it controls f3.

    Fixed engine check: Ranked first · Rf2 Bxf2#.

  18. 19...Bxf2# Checkmate

    Board fact: Black's bishop moves from e3 to f2 and delivers checkmate; White's king has no legal way to answer the attack.

    Fixed engine check: Ranked first · Bxf2#.

PGN

[Event "Amsterdam"] [Site "?"] [Date "1861.??.??"] [White "Kloos, H."] [Black "Anderssen, Adolf"] [Result "0-1"] 1. e4 e5 2. Bc4 Nf6 3. Nc3 Bc5 4. Nf3 Nc6 5. d3 d6 6. h3 h6 7. a3 Bb6 8. O-O g5 9. Be3 g4 10. hxg4 Bxg4 11. Ne2 Bxf3 12. gxf3 Rg8+ 13. Kh1 Nxe4 14. Ng3 Qh4+ 15. Kg2 Rxg3+ 16. fxg3 Qxg3+ 17. Kh1 Qh3+ 18. Kg1 Bxe3+ 19. Rf2 Bxf2# 0-1

Sources and checking

Score source: Chess Database, version 1 by Ana Schaigorodsky (2016), licensed under CC BY 4.0. LibreChess selected the exact score identified by sha256:e7f34e99d0e9656623c744d31c1029756330e412f8830a4af395432085a1446c and pins it in the selection manifest.
Exact Figshare tags:
White="Kloos, H"; Black="Anderssen, Adolf"; Event="Amsterdam"; Date="1861.??.??"; Result="0-1".
Reviewed display mapping: white Kloos, H → Kloos, H.. LibreChess parsed the main line with chess.js and stores normalised SAN. Source comments, side variations and termination detail were not retained.

LibreChess checks every SAN move with chess.js and compares the result and move sequence with a stored reference. The engine comparison was calculated offline from the fixed settings above; it is not a source for historical claims. No termination is inferred where the imported score does not preserve one.

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