1 G. F. Anderson 5th HM British Chess Federation Tourney No.55 1946-47 Selfmate in 2

1 is a fine example of a complex strategic selfmate, with interest centred around the post-key play. The arrangement on the sixth rank is called a half-pin, since if either white piece leaves the line the other will be pinned, while the pieces at a1 and c3 form a battery, poised to discover check. With lines around his king guarded, White needs to force a double check, hence the key 1.Ba7, which threatens 2.f3+ Rxf3. A random check from the battery is met by 2.Qe5+ Bxe5. After 1…Rc5+ 2.Qe5+ does not work, as Black could reply 2…Rxe5, but 2.Qd4+ Bxd4 exploits both the rook's closure of the white bishop's guard and the pin of the e6 knight. 1…Rb6 defends by cutting the bishop's control of e3, but as it also no longer controls d4 White can continue with 2.Qd3+ Rxd3, again leaving the knight pinned. 1…Rxa7 removes the rook from the sixth rank, allowing 2.Qc6+ Rxc6, another pin-mate. Finally 1…Bf5 defends by preventing the threat from giving a double check, but places a guard on e6 which allows White to complete the half-pin with 2.Sc5+ Rxc5. Great variety from a remarkably light setting.

2 D. G. McIntyre Alain White Album 1920 Selfmate in 3

Battery play is much more common in the selfmate than the directmate. In McIntyre's intricate problem no fewer than six batteries fire, four white and two black. The problem is also notable for the mobility of the white king. The key 1.Re7 blocks a potential flight square and threatens 2.Kd5+ Kxb5 3.Ke6+ Sc5 mate. After 1…Bb1 White exploits the potential pin of the white bishop by 2.Kc3+ Ka5 3.Kxd3+ Sd2. 1…d2 gives a flight at a5, leading to 2.Kd3+ Ka5 3.b6+ Sc5. There is a sideline variation which brings the key piece into play: 1...dxc2 2.Sb6+ axb6 3.Ra7+ Sa5.

3 Y. Afek The Problemist 1982 Selfmate in 2

3 is an example of a selfmate mutate. Continuations are set for both black pawn moves. If 1…exd5 the bishop must unguard the rook and block e2: 2.Be2 dxe4. After 1…e5 Black is stalemated, so this time the knight must block e2: 2.Se2 g1 any. White has no available mating move, and the key 1.Re1 causes the continuations to be reciprocally changed. 1…exd5 leaves Black stalemated this time, hence 2.Se2 g1 any, while after 1…e5 the pawn will advance to e4, so White must play 2.Be2. The problem is worth comparing with No.7 in the article on three-movers.

4 J. Sledziewski 1st Place Warsaw v Silesia 1959 Selfmate in 2

The key of 4, 1.Bg1, threatens 2.Qb7+ Bxb7. Three of Black's defences block the long diagonal and unpin the queen, which responds by checking to draw the unpinner off the line. 1…Sc6 2.Qa5+ Sxa5; 1…Rf3 Qd3+ Rxd3; 1…Rg2 2.Qa2+ Rxa2. This standard selfmate idea is called the Dentist theme, from the way the black piece is extracted from the newly formed battery line. There are two further variations 1…Sc8 2.Rb6+ Sxb6 and 1…Sxd5 2.Rxd6+ Sb6, but the main point of the problem lies in a number of thematic tries, that is attempted keys which are refuted by a single defence. Some tries fail because the bishop interferes with a line which must be kept open to allow the above variations to operate. 1.Bc5? is refuted by 1…Sc6!, since 2.Qa5+ is no longer playable; similarly 1.Bd4? and 1.Be3? are met by 1…Rf3! and 1.Bf2? fails to 1…Rg2! In addition 1.Ba7? and 1.Bc7? fail to 1…Rxb8+! because of the unwanted guard placed on b8.

Modern directmate themes based on relationships between moves have been transferred to the selfmate.
In the Dombrovskis theme, defences which defeat try threats lead paradoxically to those very white moves after the key (for an example in a directmate see problem 8 in the article on three-movers).

5 S. Seider 2nd Prize Bulgaria 1300 Years Tourney 1982-83 Selfmate in 2

In 5 White must force the bishop to move, and in two tries he dismantles his batteries in order to prevent checks at c4 being double checks. 1.Ba7? threatens 2.Sdc4+ Bxc4. 1…Kxd6 is met by 2.Sec4+ Bxc4, but 1…Rc7! refutes. 1.Rf2? threatens 2.Sec4+ Bxc4, but 1…Se4! defends by cutting the queen's guard of d5. The key 1.Qc6! threatens 2.Qc5+ Bd5 and now the try refutations return as defences. After 1…Rc7 2.Sdc4+ forces 2…Bxc4 because the rook has eliminated the double check. Similarly 1…Se4 leads to 2.Sec4+ Bxc4. A very clear, easily understood scheme.

The logical school which dominates directmate more-movers has its equivalent in selfmates
(for an explanation of logical problems see the article on more-movers).

6 F. Hoffmann 1st Prize DSV-Problem Tourney 1979 Selfmate in 7

In 6 White's aim is to force Sfe4 mate, but an immediate queen check at h1 fails to 1…Sd5+. White can force the king to block d5 with 1.Bd5+ Kxd5, but after 2.Qh1+ Black can play Sce4+. A five-move foreplan transfers the white rook to b5, anticipating a pin along the rank. 1.Ba5 Bg7 2.Sa7+ Kd6 3.Sc8+ Kc6 4.Rb6+ Kc7 5.Rb5+ Kc6 and now the mainplan works: 6.Bd5+ Kxd5 7.Qh1+ Se4.

7 G. F. Anderson Natal Mercury 1915 Selfmate in 4

Some selfmates feature ideas designed to appeal more to the eye than the mind. Anderson's king dances round the rook, such a geometric trip being known by the German term rundlauf. 1.Kc4 axb5+ 2.Kd3 e2 3.Ke4+ K any 4.Kd5+ Sf4.

8 B. Lindgren and H. P. Rehm 1st Prize Probleemblad 1980 Selfmate in 13

Lengthy single-line selfmates often contain repetitive manoeuvres. In 8 the black trio are shepherded down the board with careful timing, as the knight must be controlled by a sequence of pins. A problem to raise a smile. 1.Ke3 c5 2.Qb8+ Kc6 3.Rh6+ Se6 4.Kd2 c4 5.Rd6+ Kc5 6.Rh5+ Sg5 7.Kc1 c3 8.Qb6+ Kc4 9.Rh4+ Se4 10.Rg4! c2 11.Rd4+ Kc3 12.Rg3+ Sxg3 13.Se2+ Sxe2.

The Bohemian style (see the article on three-movers), which aims to combine aesthetic mates, finds ample scope in the selfmate.

9 F. J. Prokop British Chess Magazine 1951 Selfmate in 8

9 is a typical Bohemian echo selfmate, with the mating force being deftly guided into position. With such a mobile black force checks are necessary all the way. The two underpromotions add interest. 1.Kc7+ Rb8 2.h8R+ Ke7 3.Rh7+ Ke8 4.Bb5+ Bxb5 5.Qe4+ Kf8 6.Rh8+ Kg7 7.Bc3+ Bxc3 8.Qe5+ Bxe5; 1…Ke7 2.Kc6+ Rb7 3.Bb4+ Bxb4 4.Qe3+ Kf6 5.Sg4+ Kg7 6.h8B+ Kh7 7.Bd3+ Bxd3 8.Qe4+ Bxe4.

A reflexmate is a selfmate with the added condition that either side must mate on the move if possible.

10 C. G. Rains The Problemist 1972 (version) (a) Selfmate in 2 (b) Reflexmate in 2

A twin which lucidly illustrates the difference between a selfmate and a reflexmate. The only possible mate after 1…Bh7 is 2…Bf5. As a selfmate White must force the bishop to f5, so the key is 1.Rf5, setting up a battery for 1…Bh7 2.Se6+ Bxf5. As a reflexmate 1.Rf5 is too strong, because after 1…Bh7 the reflex condition forces White to continue with 2.Sg6 mate. However White can remove rook and bishop guards on the diagonal leading to the king by 1.Re5 Bh7 2.Re6, and now Black must play 2...Bf5. Note how other white moves would fail: 1.Rd5? Bh7 2. Rd1 mate (not 2.Rd7?); similarly 1.Bb7? Bh7 2.Bg2 mate (not 2.Rf5?), and 1.Ba6? Bh7 2.e4 mate (again not 2.Rf5?).

Reflexmates are often more economical than selfmates, because there is not the same need to control the black king.

11 G. F. Anderson The Problemist 1970 Reflexmate in 3

In 11 White would like to play the critical manoeuvre 1.Qd5+ followed by 2.Se4 to force 2…h1Q mate, but with the bishop at f6 Black would reply 1…Kf8, forcing 2.Rxb8 mate. White opens 1.Be7 to threaten 2.Qd5+. As Qd5 must deliver check, to prevent the pawn from promoting too soon, Black can defend by moving the king. After 1…Kg7 or Kh8 White plays a continuation which matches the threat: 2.Qa1+ K any 3.Sd1 h1Q; similarly after 1...Kh7 2.Qb1+ followed by 3.Sd1. 1...f3 opens bishop guards on g3 and h2, leading to 2.Bh4 any 3.Qg1 hxg1S mate.

Many modern reflexmates present complex variations, abandoning tries which fail because White must give mate.

12 N. A. Macleod 4th HM Anderson Memorial Tourney 1986 Reflexmate in 2

12 illustrates a variety of unpins of the black knight in a light setting. 1.Qg8 unguards c5 and threatens 2.Scd5, forcing 2…Sc5 mate. The bishop can block c5, but White exploits the new guard on b4: 1…Bc5 2.Sbc6 Sxc3. 1…Bxc3 removes the threat knight but again guards b4. This time White must be careful not to unpin his rook, hence 2.Sbd5 Sc5. Finally a variation in which the rook is unpinned: 1…Rd7 2.Rd5 Sxc3.

In some problems the reflex condition is applied only to black. Such problems are called semireflexmates.