Checkmate

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This article uses algebraic notation to describe chess moves.

Checkmate (frequently shortened to mate) is a situation in chess (and in other boardgames of the chaturanga family) in which one player's king is threatened with capture (in check) and there is no way to meet that threat. Delivering checkmate is the ultimate goal in chess: a player who is checkmated loses the game (the king is never actually captured – the game ends as soon as the king is checkmated). In practice, most players resign an inevitably lost game before being checkmated.

If a king is under attack but the threat can be met, then the king is said to be in check, but is not in checkmate. If a player is not in check but has no legal move (that is, no valid move that would not put the king in check), the result of the game is stalemate, and the game ends in a draw. (See Rules of chess.)

Contents 1 Origin of the word 2 Examples 3 Two major pieces 4 Basic checkmates 4.1 King and queen 4.2 King and rook 4.3 King and two bishops 4.4 King, bishop and knight 5 The case of two or more knights 6 Rare checkmate positions 6.1 Stamma's mate 6.2 Unusual checkmate positions 7 Quick checkmates 8 See also 9 Notes 10 References 11 External links

[edit] Origin of the word

The term checkmate is an alteration or Hobson-Jobson of the Persian phrase "Shah Mat" which means, literally, "the King is ambushed" (or "helpless" or "defeated"). It does not literally mean "the King is dead", although that is a common misconception.^[1]

Moghadam traced the etymology of the word mate. It comes from a Persian word mandan, meaning "to remain", which is cognate with the Latin word manco. It means "remained" in the sense of "abandoned" and the formal translation is "surprised", in the military sense of "ambushed" (not in the sense of "astonished"). So the king is in mate when he is ambushed, at a loss, or abandoned to his fate.(Davidson 1981:70-71)

The term checkmate has come to mean in modern parlance an irrefutable, strategic victory.

[edit] Examples

A checkmate may occur in only two moves with all of the pieces still on the board (as in Fool's mate, in the opening phase of the game), in a middlegame position (as in the Game of the Century between Donald Byrne and Bobby Fischer), or after many moves with as few as three pieces in an endgame position.

[edit] Two major pieces

Two major pieces (queens or rooks) can easily force checkmate on the edge of the board, even without the help of their king. The process is to put the two pieces on adjacent ranks or files and gradually force the king to the side of the board, where one piece keeps the king on the edge of the board while the other delivers checkmate (Pandolfini 1988:18-20).

In the first diagram, White checkmates easily by forcing the black king to the edge a rank at the time or a file at the time:

• 1. Qg5+ Kd4
• 2. Rf4+ Ke3
• 3. Qg3+ Ke2
• 4. Rf2+ Ke1
• 5. Qg1# (second diagram) (Silman 2007:7-8).

The checkmate with two queens or with two rooks is similar.

Checkmate can be forced in the center of the board with two rooks and a king, or with a queen, rook, and king, while two queens are able to force checkmate in the center without the help of the king.

[edit] Basic checkmates

Here are the common fundamental checkmates when one side has only his king and the other side has only the minimum material needed to force checkmate, i.e. (1) one queen, (2) one rook, (3) two bishops on opposite colors, or (4) a bishop and a knight. The king must help in accomplishing all of these checkmates. If the superior side has more material, checkmates are easier.

The checkmate with the queen is the most important, but it is also very easy to achieve. It often occurs after a pawn has queened. The next most important one is the checkmate with the rook, and it is also very easy to achieve. The checkmates with the two bishops and with a bishop and knight are not nearly as important, since they only occur infrequently. The two bishop checkmate is fairly easy to accomplish, but the bishop and knight checkmate is difficult and requires precision.

[edit] King and queen

The first two diagrams show representatives of the basic checkmate positions with a queen, which can occur on any edge of the board. Naturally, the exact position can vary from the diagram. In the first of the checkmate positions, the queen is directly in front of the opposing king and the white king is protecting its queen. In the second checkmate position, the kings are in opposition and the queen mates on the rank (or file) of the king. See Wikibooks - Chess/The Endgame for a demonstration of how the king and queen versus king mate is achieved.

With the side with the queen to move, checkmate can be forced in at most ten moves from any starting position, with optimal play by both sides, but usually fewer moves are required (Fine & Benko 2003:1-2). (Müller & Lamprecht 2001:16). In positions in which a pawn has just promoted to a queen, at most nine moves are required (Levy & Newborn 1991:144). In this position, White checkmates by confining the black king to a rectangle and shrinking the rectangle to force the king to the edge of the board:

• 1. Qf6 Kd5
• 2. Qe7 Kd4
• 3. Kc2 Kd5
• 4. Kc3 Kc6
• 5. Kc4 Kb6
• 6. Qd7 Ka6
• 7. Qb5+ Ka7
• 8. Kc5 Ka8
• 9. Kc6 Ka7
• 10. Qb7# (Seirawan 2003:4-5).

The winning side must be careful to not stalemate the opposing king. There are two general types of stalemate positions that can occur, which the winning side must avoid (Fine & Benko 2003:2).

[edit] King and rook

The first diagram shows the basic checkmate position with a rook, which can occur on any edge of the board. The black king can be on any square on the edge of the board, the white king is in opposition to it, and the rook can check from any square on the rank or file (assuming that it can not be captured). The second diagram shows a slightly different position where the kings are not in opposition but the defending king must be in a corner.

With white to move, checkmate can be forced in at most sixteen moves from any starting position (Fine & Benko 2003:2). Again, see Wikibooks - Chess/The Endgame for a demonstration of how the king and rook versus king mate is achieved.

In this position, White checkmates by confining the black king to a rectangle and shrinking the rectangle to force the king to the edge of the board:

• 1. Kd3+ Kd5
• 2. Re4 Kd6
• 3. Kc4! Kc6
• 4. Re6+ Kc7
• 5. Kc5 Kd7
• 6. Kd5 Kc7
• 7. Rd6 Kb7
• 8. Rc6 Ka7
• 9. Kc5 Kb7
• 10. Kb5 Ka7
• 11. Rb6 Ka8
• 12. Kc6 Ka7
• 13. Kc7 Ka8
• 14. Ra6# (second checkmate position) (Seirawan 2003:1-4)

There are two stalemate positions to watch out for: (Fine & Benko 2003:2-3):

[edit] King and two bishops

Here are the two basic checkmate positions with two bishops (on opposite colors), which can occur in any corner. (Two bishops or more on the same color cannot checkmate.) The first is a checkmate in the corner. The second one is a checkmate in a side square next to the corner square. With the side with the bishops to move, checkmate can be forced in at most nineteen moves (Müller & Lamprecht 2001:17).

It is not too difficult for two bishops to force checkmate, with the aid of their king. Two principles apply:

• The bishops are best when they are near the center of the board and on adjacent diagonals. This cuts off the opposing king.
• The king must be used aggressively, in conjunction with the bishops.

In the position from Seirawan, White wins by first forcing the black king to the side of the board, then to a corner, and then checkmates. It can be any side of the board and any corner. The process is:

• 1. Ke2 Ke4 (Black tries to keep his king near the center)
• 2. Be3 Ke5 (forcing the king back, which is done often)
• 3. Kd3 Kd5
• 4. Bd4 Ke6
• 5. Ke4 Kd6 (Black tries a different approach to stay near the center)
• 6. Bc4 (White has a fine position. The bishops are centralized and the king is active.)
• 6... Kc6 (Black avoids going toward the side)
• 7. Ke5 Kd7 (Black is trying to avoid the a8 corner)
• 8. Bd5 (keeping the black king off c6)
• 8... Kc7
• 9. Bc5 Kd7
• 10. Bd6! (an important move that forces the king to the edge of the board)
• 10... Ke8 (Black is still avoiding the corner)
• 11. Ke6 (now the black king cannot get off the edge of the board)
• 11... Kd8
• 12. Bc6 (forcing the king toward the corner)
• 12... Kc8 (Black's king is confined to c8 and d8. The white king must cover a7 and b7)
• 13. Kd5 (13. Ke7? is stalemate)
• 13...Kd8
• 14. Kc5 Kc8
• 15. Kb6 Kd8 (Now White must allow the king to move into the corner)
• 16. Bc5 Kc8
• 17. Be7! (an important move that forces the king toward the corner)
• 17... Kb8
• 18. Bd7! (the same principle as the previous move)
• 18... Ka8
• 19. Bd8 (White must make a move that gives up a tempo. This move is one, along with Bc5, Bf8, Be6, or Ka6.)
• 19... Kb8
• 20. Bc7+ Ka8
• 21. Bc6#, as in the first diagram in this section (Seirawan 2003:5-7).

Note that this is not the shortest forced checkmate from this position. Müller and Lamprecht give a fifteen move solution, however it contains an inaccurate move by Black (according to endgame tablebases) (Müller & Lamprecht 2001:17). With optimal play by both sides, checkmate in this position requires seventeen moves. The longer variation is more instructive.

[edit] King, bishop and knight

Main article: Bishop and knight checkmate

This checkmate is the most difficult to force, because these two pieces cannot form a linear barrier to the enemy king from a distance. Also, the checkmate can be forced only in a corner that the bishop controls.

Here are the two basic checkmate positions with a bishop and a knight, or the bishop and knight checkmate. The first position is a checkmate by the bishop, with the king in the corner. The second position is a checkmate by the knight, with the king in a side square next to the corner. Alternatively, the knight can be on c6 or d7 in the second position.

With White to move, checkmate can be forced in at most thirty-three moves from any starting position (Müller & Lamprecht 2001:19), except those in which the black king is initially forking the bishop and knight and it is not possible to defend both. However, the mating process requires accurate play, since a few errors could result in a draw either by the fifty move rule or stalemate.

[edit] The case of two or more knights

Main article: Two knights endgame

It is impossible to force checkmate with a king and two knights, although checkmate positions are possible (see the first diagram). In the second diagram, if Black plays 1... Ka8? White can checkmate with 2. Nbc7#, but Black can play 1... Kc8 and escape the threat. The defender's task is easy — he simply has to avoid moving into a position in which he can be checkmated on the next move, and he always has another move available in such situations (Speelman, Tisdall & Wade 1993:11).

In the third diagram, White can play 1. Nc6+ Ka8, but now if White plays 2. Nb5 threatening 3. Nc7#, Black is stalemated. It is sometimes possible to force checkmate with two knights against a pawn, because in some positions, having a pawn removes this stalemate defence.

Three knights and a king can force checkmate against a lone king. Four knights can force checkmate against a lone king even without their own king's participation. These situations are generally only seen in chess problems, since one or more of the knights must be a promoted piece, and there is very rarely a reason (e.g., avoidance of stalemate) to promote a pawn to anything other than a queen (see underpromotion).

Under some circumstances, two knights and a king can force checkmate against a king and pawn (or rarely more pawns). The winning plan, quite difficult to execute in practice, is to blockade the enemy pawn(s) with one of the knights, maneuver the enemy king into a stalemated position, then bring the other knight over to checkmate. (See Two knights endgame.)

[edit] Rare checkmate positions

In some rare positions it is possible to force checkmate with a king and bishop versus a king and pawn or a king and knight versus a king and pawn.

[edit] Stamma's mate

In the diagram showing Stamma's mate (named for Philipp Stamma), White to move wins (Emms 2004:122):

• 1. Nb4+ Ka1
• 2. Kc1 a2
• 3. Nc2#

White also wins if Black is to move first:

• 1. ... Ka1
• 2. Nc1 a2
• 3. Nb3#

This checkmate has occurred in actual games, see the game Nogueiras-Gongora [1] from the 2001 Cuban Championship, which proceeded

• 81. Kc2 Ka1
• 82. Nc5 Ka2 (if 82... a2 then 83. Nb3#)
• 83. Nd3 (reaching the first position)
• 83... Ka1
• 84. Nc1 a2
• 85. Nb3# (Snape 2003:55)

[edit] Unusual checkmate positions

There are also positions in which a king and knight or bishop can checkmate a king and bishop, but checkmate cannot be forced (see the diagrams for some examples). Nevertheless, it keeps these material combinations from being ruled a draw because of "insufficient mating material" or "impossibility of checkmate".

[edit] Quick checkmates

Some common or notable mating patterns have names of their own. Apart from the aforementioned fool's mate, these include scholar's mate, smothered mate, the back rank mate, Boden's mate, epaulette mate, and Légal's mate (see below).

Some opening traps involve an early checkmate. These include:

• Benoni Defense 1.d4 c5 2.d5 e6 3.Nc3 exd5?! 4.Nxd5 Ne7 5.Bg5 h6 6.Bh4 Qa5+ 7.c3 Nf5?? 8.Qa4!! Qxa4 9.Nc7# 1-0 Yermolinsky-Tate, Reno 2001
• Blackburne Shilling Gambit 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nd4?! 4.Nxe5!? Qg5! 5.Nxf7?? Qxg2 6.Rf1 Qxe4+ 7.Be2 Nf3#
• Budapest Gambit 1.d4 Nf6 2.c4 e5 3.dxe5 Ng4 4.Bf4 Nc6 5.Nf3 Bb4+ 6.Nbd2 Qe7 7.a3 Ngxe5! 8.axb4?? Nd3#
• Budapest Gambit 1.d4 Nf6 2.c4 e5 3.d5?! Bc5 4.Bg5? Ne4! 5.Bxd8?? Bxf2#
• Caro-Kann Defence 1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Nxe4 Nd7 5.Qe2 Ngf6?? 6.Nd6# Alekhine-Four Amateurs, simultaneous exhibition, Palma de Mallorca 1935
• Caro-Kann Defence (from above) 5.Bc4 Ngf6 6.Ng5 e6 7.Qe2 Nb6 8.Bd3 h6 9.N5f3 c5 10.dxc5 Nbd7!? 11.b4 b6 12.Nd4! bxc5?? 13.Nc6! Qc7 14.Qxe6+! (1-0 Perenyi-Eperjesi, Budapest 1974) fxe6 15.Bg6#
• Caro-Kann Defence 1.e4 c6 2.Nc3 d5 3.Nf3 dxe4 4.Nxe4 Bf5?! 5.Ng3 Bg6? 6.h4 h6 7.Ne5 Bh7 8.Qh5! g6 9.Bc4! e6 10.Qe2 Nf6?? 11.Nxf7! Kxf7 12.Qxe6+ (1-0 Alekhine-Bruce, Plymouth 1938) Kg7 13.Qf7#
• Caro-Kann Defence 1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Nxe4 Nf6 5.Qd3!? e5?! 6.dxe5 Qa5+ 7.Bd2 Qxe5 8.0-0-0! Nxe4?? 9.Qd8+!! Kxd8 10. Bg5++ (Réti-Tartakower, Vienna 1910) 10...Ke8 11.Rd8# or 10...Kc7 11.Bd8#
• Dutch Defense 1.d4 f5 2.Bg5 h6 3.Bh4 g5 4.Bg3 f4? 5.e3 h5 (5...fxg3?? 6.Qh5#) 6.Bd3!? Rh6?? 7.Qxh5+! Rxh5 8.Bg6# Teed-Delmar, New York 1896
• Dutch Defense 1.d4 f5 2.h3 Nf6 3.g4 fxg4 4.hxg4 Nxg4 5.Qd3 Nf6?? 6.Rxh7! Rxh7 7.Qg6#
• Englund Gambit 1.d4 e5?! 2.dxe5 Nc6 3.Nf3 Qe7 4.Bf4 Qb4+ 5.Bd2 Qxb2 6.Bc3?? Bb4 7.Qd2 Bxc3 8.Qxc3 Qc1#
• From Gambit 1.f4 e5 2.fxe5 d6 3.exd6 Bxd6 4.Nf3 (4.b3?? Qh4+ 5.g3 Qxg3+ 6.hxg3 Bxg3# Pantelidakis-Rhine, Chicago 1974) g5 5.h3?? Bg3# Napetschnig-Rhine, Chicago 1977
• Grünfeld Defense 1.d4 Nf6 2.c4 g6 3.Nc3 d5 4.cxd5 Nxd5 5.e4 Nxc3 6.bxc3 Bg7 7.Bc4 c5 8.Ne2 cxd4 9.cxd4 Nc6 10.Be3 Qa5+!? 11.Bd2 Qa3 12.Rb1 0-0 13.d5? Ne5 14.Bb4? Qf3!! 15.gxf3?? Nxf3+ 16.Kf1 Bh3#
• Marshall Defense 1.d4 d5 2.c4 Nf6?! 3.cxd5 Nxd5 4.Nf3 Nc6? 5.e4 Nf6 6.Nc3 Bg4 7.d5 Ne5? 8.Nxe5! Bxd1 9.Bb5+ c6 10.dxc6 Qc7?? 11.cxb7+ Kd8 (after 11...Qd7 and 11...Nd7, White mates, or forces mate, with 12.bxa8(Q) or bxa8(R)) 12.Nxf7#
• Nimzowitsch Defense 1.e4 Nc6 2.d4 d5 3.exd5 Qxd5 4.Nf3 Bg4 5.Nc3 Bxf3 6.Nxd5 Bxd1 7.Nxc7+ Kd8 8.Nxa8 Bxc2 9.Bf4 Nxd4 10.Nc7? e5! 11.Bxe5?? Bb4#. Also possible is 7...Kd7 8.Nxa8 Bxc2 9.Bf4 e5 10.dxe5 Bb4+ 11.Ke2 Nge7 12.e6+ fxe6 13.Nc7?? Nd4+ 14.Ke3 Nef5# Kiss-Barcza, Debrecen 1930.
• Owen's Defense 1.e4 b6 2.d4 Bb7 3.Bd3 f5?! 4.exf5! Bxg2 5.Qh5+ g6 6.fxg6! Nf6?? 7.gxh7+! Nxh5 8.Bg6# Greco-N.N., Rome 1619
• Philidor's Defense 1.e4 e5 2.Nf3 d6 3.Bc4 Bg4?! 4.Nc3 g6? 5.Nxe5! Bxd1?? 6.Bxf7+ Ke7 7.Nd5# Légal-Saint Brie, Paris 1750. This mating pattern is now called Légal's mate.
• Richter-Veresov Attack 1.d4 Nf6 2.Nc3 d5 3.Bg5 c5!? 4.Bxf6 exf6!? 5.dxc5 d4 6.Ne4 Bf5 7.Ng3? Bxc5! 8.Nxf5? Qa5+! 9.c3 dxc3 10.b4 Bxb4 11.Qc2 Qxf5! 12.Qxf5?? c2# N.N.-Rhine, Chicago 1977
• Robatsch Defense 1.e4 g6 2.Nf3 d6 3.Bc4 Nd7?? 4.Bxf7+! Kxf7 5.Ng5+ Kf6 (otherwise 6.Ne6 wins the queen) 6.Qf3+ Kxg5 (6...Ke5 7.Qc3+ Kf4 8.Qg3#) 7.d4+ Kh4 8.Qh3#
• Ruy Lopez 1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.0-0 Nxe4 6.d4 exd4?! 7.Re1 d5 8.Nxd4 Bd6 9.Nxc6 Bxh2+! 10.Kh1! Qh4 11.Rxe4+! dxe4 12.Qd8+! Qxd8 13.Nxd8+ Kxd8 14.Kxh2 f5?? 15.Bg5# [2]Pandolfini-NN, 1970
• Scandinavian Defense 1.e4 d5 2.exd5 Qxd5 3.Nc3 Qa5 4.d4 c6 5.Nf3 Bg4 6.Bf4 e6 7.h3 Bxf3 8.Qxf3 Bb4 9.Be2 Nd7 10.a3 O-O-O?? 11.axb4!! Qxa1+ 12.Kd2! Qxh1 13.Qxc6+! bxc6 14.Ba6# Canal-N.N., Budapest 1934 (the "Peruvian Immortal": White sacrifices both rooks and his queen to finish with Boden's mate)
• Sicilian Defence 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 Nc6 5.Nf3 e6 6.Bc4 Qc7 7.0-0 Nf6 8.Qe2 Ng4! 9.h3?? Nd4! (winning White's queen, at least) 10.Nxd4? Qh2# (the Siberian Trap)
• Sicilian Defence 1.e4 c5 2.d4 cxd4 3.c3 d5 4.exd5 Qxd5 5.Nf3?! Bg4 6.Qa4+ Nc6 7.Nxd4 Bd7 8.Nb5? 0-0-0! 9.Nxa7+?? Nxa7 10.Qxa7 Qd1+!! (0-1 Dutch-Sugden, London 1964) 11.Kxd1 Bg4+ 12.Kc2 Bd1# or 12.Ke1 Rd1# (an ending strikingly similar to Réti-Tartakower, Vienna 1910, cited above)
• Sicilian Defence 1.e4 c5 2.Nf3 Nf6 3.e5 Nd5 4.Nc3 e6 5.Nxd5 exd5 6.d4 Nc6 7.dxc5 Bxc5 8.Qxd5 Qb6 9.Bc4 Bxf2+ 10.Ke2 O-O 11.Rf1 Bc5 12.Ng5 Nd4+ 13.Kd1 Ne6 14.Ne4 d6 15.exd6 Bxd6?? 16.Nxd6 Rd8 17.Bf4! Nxf4? 18.Qxf7+ Kh8 19.Qg8+! (1-0 Unzicker-Sarapu, Siegen Olympiad 1970) Rxg8 20.Nf7#
• Sicilian Defence 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Bg5 e6 7.f4 b5 8.e5 dxe5 9.fxe5 Qc7 10.Qe2 Nfd7 11.0-0-0 Bb7 12.Qg4 Qxe5 13.Bd3 Nf6? 14.Bxf6 Qxf6? 15.Rhe1 h5 16.Nxe6! Be7 (16...hxg4 17.Bxb5+! Ke7 (17...axb5? 18.Nc7# or 18.Nxg7#) 18.Nxf8+ Kxf8? 19.Re8#) 17.Bxb5+! axb5 18.Nc7+! Kf8 19.Rd8+! Bxd8 20.Re8# Tal-N.N., England 1974
• Three Knights Game 1.e4 e5 2.Nf3 Nc6 3.Nc3 g6 4.d4 exd4 5.Nd5 Bg7 6.Bg5 Nge7? 7.Nxd4! Bxd4?? 8.Qxd4! Nxd4 9.Nf6+ Kf8 10.Bh6#
• Two knights defense 1. e4 e5 2. Nf3 Nc6 3. Bc4 Nf6 4. Ng5 d5 5. exd5 Nxd5 6. Nxf7 Kxf7 7. Qf3 Ke8? 8. Bxd5 Bd7?? (or several other moves) 9. Qf7#
• Vienna Game 1.e4 e5 2.Nc3 Nf6 3.Bc4 Nxe4 4.Bxf7+ (4.Nxe4 d5) Kxf7 5.Nxe4 Nc6 6.Qf3+ Kg8?? 7.Ng5! Qxg5 8.Qd5#

[edit] See also

Rules of chess Check (board game) Chess endgame Chess problem Chess theory Bishop and knight checkmate Back rank checkmate

Boden's Mate Epaulette mate Fool's mate Ideal mate Légal Trap

Model mate Pawnless chess endgames Pure mate Scholar's mate Smothered mate

[edit] Notes

[edit] References

• Davidson, Henry (1981), A Short History of Chess (1949), McKay, ISBN 0-679-14550-8 
• Emms, John (2004), Starting Out: Minor Piece Endgames, Everyman Chess, ISBN 1-85744-359-4 
• Fine, Reuben & Benko, Pal (2003), Basic Chess Endings (1941), McKay, ISBN 0-8129-3493-8 
• Levy, David & Newborn, Monty (1991), How Computers Play Chess, Computer Science Press, ISBN 0-7167-8121-2 
• Müller, Karsten & Lamprecht, Frank (2001), Fundamental Chess Endings, Gambit Publications, ISBN 1-901983-53-6 
• Pandolfini, Bruce (1988), Pandolfini's Endgame Course, Fireside, Simon & Schuster, ISBN 978-0-671-65688-1 
• Seirawan, Yasser (2003), Winning Chess Endings, Everyman Chess, ISBN 1-85744-348-9 
• Silman, Jeremy (2007), Silman's Complete Endgame Course: From Beginner to Master, Siles Press, ISBN 1-890085-10-3 
• Snape, Ian (2003), Chess Endings Made Simple: How to Approach the Endgame with Confidence, Gambit Publications, ISBN 1-901983-97-8 
• Speelman, Jon; Tisdall, Jon & Wade, Bob (1993), Batsford Chess Endings, B. T. Batsford, ISBN 0-7134-4420-7 

[edit] External links

• Interactive checkmate practice
• Checkmate examples at SilverPawn.com