The Immortal Game is perhaps the most famous game ever in the history of chess. It features several large sacrifices by white, who checkmates black with only a few pieces left. The game has been subject to substantial and very detailed analysis by both Grandmasters and computers alike, without any clear verdict as to whether all the sacrifices are completely correct. Nonetheless, it is an amazing game to replay.
The game starts:
1. e4 e5
2. f4 exf4
This is the King's Gambit, where White gives up a pawn early for rapid development, open lines for his pieces, and a possible attack on the king. Although one of the most popular openings in the nineteenth century, it is now unpopular at the professional levels, as defensive techniques have improved considerably.
3. Bc4 Qh4+
4. Kf1 (diagram 1)
With his third move, white says he doesn't mind losing the right to castle as long as he gets his pieces developed quickly. In the 19th century, there was much more focus on aggressive development, and players were more likely to sacrifice pawns or even pieces to get an active position. By today's standards, Anderssen and Kieseritzky's style of play would have been considered extravagant and not necessarily the best, but nonetheless very entertaining.
4. ... b5!?
An interesting, and obscure, counter-gambit by black, who wants to get his queenside pieces developed quickly. This move is almost never seen today and is regarded as somewhat unsafe for black, but there is no immediate refutation.
5. Bxb5 Nf6
We now see that Black's third move, ...Qh4+, has its problems. Black now has to waste a move moving his queen to safety while white can bring out his forces with gain of time.
6. ... Qh6 (Diagram 2)
White takes a moment to solidify his centre and also opens up a diagonal for his bishop on c1. The German grandmaster Robert Huebner, who made a detailed analysis of the game, suggests that 7. Nc3 is slightly better.
7. ... Nh5
This move threatens a check at g3, forking the king and rook, when the h-pawn can't take because of ...Qxh1. However, this threat is easily parried, and the black knight will find itself on a rather useless square.
Anderssen dissolves black's last threat and prepares to move his knight to f5, where it will dominate the centre.
8. ... Qg5
9. Nf5 c6 (Diagram 3)
Kieseritzky gains a tempo by attacking the bishop, although analysis has shown that 8. ... g6 might have been better, by attacking the annoying knight.
10. g4 Nf6
Anderssen decides the time is ripe for a sacrifice. As we will see shortly, white gives up a bishop but in return will push black's queen and knight to poor squares, giving white the edge.
11. ... cxb5?
According to Huebner, this was the critical mistake of the game; black gets too greedy for material. The Grandmaster instead recommends 10. ...h5.
12. h4! (Diagram 4)
Black's queen is boxed in; neither white pawn can be taken because they are well defended by the queen at d1 and the knight at f5.
12. ... Qg6
13. h5 Qg5
White has two threats now: the first is to play Bxf4, trapping black's queen and winning material. The other is to play e5, attacking black's knight and the rook at a8 simultaneously, and winning material.
14. ... Ng8 (Diagram 5)
Ugly, but forced. This is the only move that can parry both threats at once, but now black's knight is sitting largely useless on its starting square.
15. Bxf4 Qf6
16. Nc3 Bc5
Black finally gets a piece developed, but it is too little too late.
This threatens a fork at c7, winning the rook. The early 20th-century master Richard Reti suggests 17. d4 as an improvement, further overtaking the centre and forcing the black bishop to move.
17. ... Qxb2
Black may as well accept the offered pawn. Note that all of white's minor pieces and queen are on powerful, central squares and he has complete control of the centre, whereas black has only one piece (the queen) developed, and even it is out of the action.
18. Bd6! (?) (Diagram 6)
The most critical move of the game. White leaves both of his rooks unprotected on the back rank for black to take, in return for a devastating attack on Kieseritzky's king. Most annotators give the move two exclamation marks, but Huebner provides three other moves he says are better (18. d4, 18. Be3, and 18. Re1), and gives the game move a question mark. Nevertheless, it leads to the following brilliant ending.
18. ... Bxg1
Computer analysis suggests that 18. ... Qxa1 is a better move. Wilhelm Steinitz provides the line 18. ... Qxa1 19. Ke2 Qb2 20. Kd2 Bxg1, where black has massive amounts of material but pieces on useless squares.
White now stops the black queen from coming back on the a1-h8 diagonal and cuts it off entirely from defending the king.
19. ... Qxa1+ 20. Ke2 (Diagram 7)
A bizarre position. Black's short-lived attack, however, is now out of steam, and he cannot safely deliver any further checks on the white king. Kieseritzky finds himself in a difficult position to defend, despite being up in material and having the move.
20. ... Na6
White was threatening to play Nxg7+ followed by Bc7#. However, computer analysis now shows that white has a forced checkmate in three. Black could have prolonged the battle with 20 ... Ba6 instead, giving the king a space to run to, but 21. Nc7+ Kd8 22. Nxa6 Qxa2 (White was threatening Bc7+, Nd6+ and Qf7#) 23. Bc7+ Ke8 24. Nb4 d5 25. Nd6+ is winning.
21. Nxg7+ Kd8
The final sacrifice. Victory is in sight.
22. ... Nxf6 23. Be7# (Diagram 8)