The ending Rook and King Against King. The principle is to drive the opposing King to the last line on any side of the board.
In this position the power of the Rook is demonstrated by the first move, 1.Ra7, which immediately confines the Black King to the last rank, and the mate is quickly accomplished by: 1…Kg8 2.Kg2.
The combined action of King and Rook is needed to arrive at a position in which mate can be forced. The general principle for a beginner to follow is to keep his King as much as possible on the same rank, or, as in this case, file, as the opposing King.
When, in this case, the King has been brought to the sixth rank, it is better to place it, not on the same file, but on the one next to it towards the centre. 2…Kf8 3.Kf3 Ke8 4.Ke4 Kd8 5.Kd5 Kc8 6.Kd6. Not 6.Kc6, because then the Black King will go back to d8 and it will take much longer to mate. 6…Kb8. If now the King moves back to d8, 7.Ra8# mates at once. 7.Rc7 Ka8 8.Kc6 Kb8 9.Kb6 Ka8 10.Rc8#.
It has taken exactly ten moves to mate from the original position.
On move 5 Black could have played 5…Ke8, and, according to principle, White would have continued 6.Kd6 Kf8 (the Black King will ultimately be forced to move in front of the White King and be mated by Ra8); 7.Ke6 Kg8 8.Kf6 Kh8 9.Kg6 Kg8 10.Ra8#.
Since the Black King is in the centre of the board, the best way to proceed is to advance your own King thus: 1.Ke2 Kd5 2.Ke3. As the Rook has not yet come into play, it is better to advance the King straight into the centre of the board, not in front, but to one side of the other King. 2…Kc4.
Should the Black King move 2…Ke5, the Rook drives it back by 3.Rh5+.
3.Rh5 Kc3. If instead 3…Kb4, then 4.Kd3.
4.Rh4, keeping the King confined to as few squares as possible.
Now the ending may continue: 4…Kc2 5.Rc4+ Kb3 6.Kd3 Kb2 7.Rb4+ Ka3 8.Kc3 Ka2. It should be noticed how often the White King has moved next to the Rook, not only to defend it, but also to reduce the mobility of the opposing King. Now White mates in three moves thus: 9.Ra4+ Kb1 10.Ra5, or any square on the Rook’s file, forcing the Black King in front of the White, 10…Kc1 11.Ra1#. It has taken eleven moves to mate, and, under any conditions, I believe it should be done in under twenty. While it may be monotonous, it is worth while for the beginner to practice such things, as it will teach him the proper handling of his pieces.
Now we come to two Bishops and King against King.
Since the Black King is in the corner, White can play 1.Bd3 Kg7 2.Bg5 Kf7 3.Bf5. Already the Black King is confined to a few squares. If the Black King, in the original position, had been in the centre of the board, or away from the last row, White should have advanced his King, and then, with the aid of his Bishops, restricted the Black King’s movements to as few squares as possible. We might now continue: 3…Kg7 4.Kf2. In this ending the Black King must not only be driven to the edge of the board, but he must also be forced into a corner, and, before a mate can be given, the White King must be brought to the sixth rank and, at the same time, in one of the last two files; in this case either h6, g6, f7 or f8; and as h6 and g6 are the nearest squares, it is to either of these squares that the King ought to go. 4…Kf7 5.Kg3 Kg7 6.Kh4 Kf7 7.Kh5 Kg7 8.Bg6 Kg8 9.Kh6 Kf8. White must now mark time and move one of the Bishops, so as to force the Black King to go back to g8. 10.Bh5 Kg8 11.Be7 Kh8. Now the White Bishop must take up a position from which it can give check next move along the White diagonal, when the Black King moves back to g8. 12.Bg4 Kg8 13.Be6+ Kh8 14.Bf6#.
It has taken fourteen moves to force the mate and, in any position, it should be done in under thirty.
In all endings of this kind, care must be taken not to drift into a stale mate.
In this particular ending one should remember that the King must not only be driven to the edge of the board, but also into a corner. In all such endings, however, it is immaterial whether the King is forced on to the last rank, or to an outside file, e.g. h4 or a5, e8 or d1.
We now come to Queen and King against King. As the Queen combines the power of the Rook and the Bishop, it is the easiest mate of all and should always be accomplished in under ten moves. Take the following position:
A good way to begin is to make the first move with the Queen, trying to limit the Black King’s mobility as much as possible. Thus: 1.Qc6 Kd4 2.Kd2. Already the Black King has only one available square 2…Ke5 3.Ke3 Kf5 4.Qd6 Kg5. (Should Black play 4…Kg4, then 5.Qg6+ and mate next move.) 5.Qe6 Kh4 6.Qg6 Kh3 7.Kf3 Kh4. However the king moves the queen mates (e.g. 7…Kh2 8.Qg2#..) 8.Qg4#.
We now come to Queen and King against King. As the Queen combines the power of the Rook and the Bishop, it is the easiest mate of all and should always be accomplished in under ten moves. In this ending, as in the case of the Rook, the Black King must be forced to the edge of the board; only the Queen being so much more powerful than the Rook, the process is far easier and shorter. These are the three elementary endings and in all of these the principle is the same. In each case the cooperation of the King is needed. In order to force a mate without the aid of the King, at least two Rooks are required.