Elementary Checkmates

The Kiss of Death is a mating pattern — a chess position showing a checkmate, with only the pieces involved on the board.

It is called the Kiss of Death because the Queen delivers checkmate from a square adjacent to the opponent's King — "kissing" it, so to speak.

In its strict form, the pattern features a Queen supported by one piece against a lone King. By extension, the term is often applied to any unnamed mating pattern in which the Queen mates from a neighbouring square, regardless of which piece supports her.

The box method is a method, not a mating pattern. It is the standard procedure for converting a King-and-Queen versus lone-King endgame into checkmate. The technique takes its name from the L-shaped geometry maintained between the Queen and the enemy King throughout the manoeuvre.

How the technique works

Place your Queen a knight's move away from the enemy King — two squares in one direction, one in the perpendicular. The shape formed by the two pieces is the letter L. From this distance the Queen does two things at once:

• She controls every square the King could move to, except a small triangle behind him.
• She is herself untouchable — the King cannot capture her, because she stands one square beyond his reach.

The enemy King is thus locked inside a box. Each time he moves, you adjust your Queen to restore the L. The box shrinks with every exchange of moves, and the King is gradually driven to the edge of the board. Once he is there, your own King walks up to support the mate.

The procedure, step by step

1. Establish the L. Move your Queen to a knight's move from the enemy King.
2. Shadow the King. Whatever direction he moves, follow with a Queen move that restores knight's-move distance. The King cannot escape the box — he can only shift it.
3. Drive him to the edge. With each adjustment, the King is forced one rank closer to the edge.
4. Park the Queen one square from the edge. Once the King reaches, say, the 8th rank, move your Queen to the 7th, keeping the L horizontally. The King is now confined to a single rank.
5. Bring your King up. Walk your own King toward the action; the Queen waits (and may oscillate) on the 7th rank.
6. Deliver mate. When your King reaches a square that defends a checking square, move the Queen adjacent to the enemy King. The technique resolves into a Kiss of Death.

The lone King has no winning chances and no way to give check. He has exactly one resource: stalemate. If you ever reach a position where it is his turn, he is not in check, and he has no legal move, the game is drawn — and a full point evaporates from a position you had completely won.

This is the only way the lone King escapes, so he will steer toward it. You must steer away. In the L technique the danger appears at one precise moment: when the King reaches the edge and your Queen comes close to finishing him. Confining the King to a single rank is correct. Confining him to a single square, while your own King is still too far away to give check, is the trap.

The same picture appears in every corner: Ka8 / Qb6, Ka1 / Qb3, Kh1 / Qg3.

Notice what went wrong. The Queen took away the last square before your King was in range to cover h8. She tried to do the confining and the mating alone — and a Queen alone cannot do both.

You abandon the L only on the very last move — and you abandon it for check, not for confinement. When your King finally guards the mating square, the Queen steps in adjacent to the enemy King and the position resolves into the Kiss of Death.

The ladder mate — also called the lawnmower or staircase — is the simplest mate of all, and the one that needs no King. Two major pieces (two Rooks, or a Queen and a Rook) mate the lone King by themselves, one cutting off a rank while the other checks along the next.

The idea: one piece traps the King on a rank; the other checks him and forces him back one rank toward the edge. Then the pieces leapfrog — the first now checks, the second cuts off — climbing the board like rungs of a ladder until the King runs out of board.

• Use the two pieces on adjacent ranks (or files) to fence the King into a shrinking strip.
• When the King steps toward your pieces, simply slide the threatened Rook far down the same line — keep your distance, never offer a trade or a check you can't support.
• The lone King cannot approach two pieces working on separate lines, so no King of your own is required.

A Rook cannot mate a lone King by itself — unlike the Queen, it does not control enough squares. Here your own King is an essential partner: the Rook cuts the board in half, and the King does the herding using opposition.

The procedure

1. Cut the King off. Place the Rook on a rank or file that walls the enemy King into one part of the board.
2. March your King up. Bring your King face to face with the enemy King, one square apart — this is the opposition.
3. Check to push. With the Kings in opposition, a Rook check forces the enemy King to step back one rank — he cannot approach the Rook because your King guards the squares.
4. Re-take the opposition and repeat, driving him to the edge one rank at a time.
5. Mate on the edge. With the enemy King on the last rank and yours in opposition, the Rook checks along that rank for mate.