MESON Chess Problem Database
Problem Display
PID: 197830 (4RKQ1/4N2B/8/1ppPrN1p/2b1k3/2Rpp1P1/4P1P1/8 w - - 0 1)
Grant, Herbert W
The Observer, 1944
(First published on Sun Jun 18 1944)
#2
11 + 8
| 15239 | Valois Notebooks | 2019 |
SOLUTION
- SOUND
- Sets
- 1...Rxd5
- 2.Sxd5#
- 1...Rxf5+
- 2.Sxf5#
- 1...Re6
- 2.Qxe6#
- 1...Rxe7
- 2.Rxe7#
- 1...Ba2
- 2.exd3#
- 1...Bb3
- 2.exd3#
- 1...Bxd5
- 2.exd3#
- 1...dxe2
- 2.Rxe3#
- 1...d2
- 2.Rxe3#
- 1...b4
- 2.Rxc4#
- 1...h4
- 2.Qg4#
- 1...Rxd5
- Tries
- 1.Kg7?
- 1...Rxe7+
- 2.Rxe7#
- 1...Rxd5
- 2.Sxd5#
- 1...Rxf5
- 2.Sxf5#
- 2.Sc6#
- 1...Bxd5
- 2.exd3#
- 1...dxe2
- 2.Rxe3#
- 1...Re6
- 2.Qxe6#
- 1...Ba2
- 2.exd3#
- 1...Bb3
- 2.exd3#
- 1...d2
- 2.Rxe3#
- 1...b4
- 2.Rxc4#
- 1...h4!
- 1...Rxe7+
- 1.Sd4+?
- 1...Rf5+
- 2.Sexf5#
- 1...Kxd4!
- 1...Rf5+
- 1.Sh4+?
- 1...Rf5+
- 2.Sexf5#
- 1...Kd4!
- 1...Rf5+
- 1.Sh6+?
- 1...Rf5+
- 2.Sexf5#
- 1...Kd4!
- 1...Rf5+
- 1.Sg7+?
- 1...Rf5+
- 2.Sexf5#
- 1...Kd4!
- 1...Rf5+
- 1.Sc6?
- threat
- 2.Sfd4#
- 2.Sh4#
- 2.Sd6#
- 2.Sh6#
- 2.Sg7#
- 2.Rxe5#
- 1...Re6
- 2.Qxe6#
- 1...Re7
- 2.Sfd4#
- 2.Sh4#
- 2.Sd6#
- 2.Sh6#
- 2.Sfxe7#
- 2.Sg7#
- 2.Rxe7#
- 1...h4
- 2.Sfd4#
- 2.Sxh4#
- 2.Sd6#
- 2.Sh6#
- 2.Sg7#
- 2.Rxe5#
- 1...Rxe8+!
- threat
- 1.Sc8?
- threat
- 2.Scd6#
- 1...Re6
- 2.Qxe6#
- 1...Re7
- 2.Rxe7#
- 1...Rxe8+!
- threat
- 1.Bg6?
- 1...Rxf5+
- 2.Sxf5#
- 1...Rxd5
- 2.Sxd5#
- 1...Rxe7
- 2.Rxe7#
- 1...Bxd5
- 2.exd3#
- 1...dxe2
- 2.Rxe3#
- 1...Re6
- 2.Qxe6#
- 1...Ba2
- 2.exd3#
- 1...Bb3
- 2.exd3#
- 1...d2
- 2.Rxe3#
- 1...b4
- 2.Rxc4#
- 1...h4!
- 1...Rxf5+
- 1.Rxd3?
- threat
- 2.Sd6#
- 2.Rxe3#
- 1...Rxf5+
- 2.Sxf5#
- 1...Rxd5
- 2.Sxd5#
- 2.Rxe3#
- 1...Rxe7
- 2.Rxe3#
- 2.Rxe7#
- 1...Re6
- 2.Rxe3#
- 2.Qxe6#
- 1...Bxd3!
- threat
- 1.Qf7?
- 1...Rxd5
- 2.Sxd5#
- 1...Rxf5
- 2.Sxf5#
- 2.Sc6#
- 1...Rxe7
- 2.Rxe7#
- 1...Bxd5
- 2.exd3#
- 1...dxe2
- 2.Rxe3#
- 1...Re6
- 2.Qxe6#
- 1...Ba2
- 2.exd3#
- 1...Bb3
- 2.exd3#
- 1...d2
- 2.Rxe3#
- 1...b4
- 2.Rxc4#
- 1...h4!
- 1...Rxd5
- 1.Qh8?
- 1...Rxf5+
- 2.Bxf5#
- 1...Rxd5
- 2.Sd6#
- 1...Rxe7
- 2.Sxe7#
- 1...Bxd5
- 2.exd3#
- 1...dxe2
- 2.Rxe3#
- 1...Re6
- 2.Sd6#
- 1...Ba2
- 2.exd3#
- 1...Bb3
- 2.exd3#
- 1...d2
- 2.Rxe3#
- 1...b4
- 2.Rxc4#
- 1...h4!
- 1...Rxf5+
- 1.Kg7?
- Keys
- 1.Qg7!
- 1...Rxf5+
- 2.Bxf5#
- 1...Rxd5
- 2.Sd6#
- 1...Rxe7
- 2.Sxe7#
- 1...Bxd5
- 2.exd3#
- 1...dxe2
- 2.Rxe3#
- 1...h4
- 2.Qg4#
- 1...Re6
- 2.Sd6#
- 1...Ba2
- 2.exd3#
- 1...Bb3
- 2.exd3#
- 1...d2
- 2.Rxe3#
- 1...b4
- 2.Rxc4#
- 1...Rxf5+
- 1.Qg7!
FEATURES
- Static
- TYPE = MUTATE
- CHANGED MATES = 4
- ADDED MATES = 0
- REMOVED MATES = 0
- Sets
- R(g);XP(E)::R(I)+S(G),XR(g)
- R(g);CHECK,P_SPINR(g),XS(F)::R(I)+S(G),XR(g)
- R(g);OGATEB::QAR2(K),XR(g)
- R(g);OGATE,P_SPINR(g),XS(G)::R(I),XR(g)
- B(c);N_GUARD::P(A),XP(a)
- B(c);N_GUARD,XP(E)::P(A),XP(a)
- P(a);OGATE,XP(A)::R1(C),XP(b)
- P(a);OGATE::R1(C),XP(b)
- P(e);N_GUARD::R(C),XB(c)
- P(h);N_GUARD::QAR2(K)
- Tries
- Try
- K(J);S_FLIGHT
- Vars
- R(g);CHECK,OGATE,P_SPINR(g),XS(G)::R(I),XR(g)
- R(g);XP(E)::R(I)+S(G),XR(g)
- B(c);N_GUARD,XP(E)::P(A),XP(a)
- P(a);OGATE,XP(A)::R1(C),XP(b)
- R(g);OGATEB::QAR2(K),XR(g)
- B(c);N_GUARD::P(A),XP(a)
- P(a);OGATE::R1(C),XP(b)
- P(e);N_GUARD::R(C),XB(c)
- Refutation
- P(h);
- Try
- S(F);CHECK
- Vars
- R(g);CHECK,P_SPINR(g)::R(I)+S(G),XR(g)
- Refutation
- K(d);P-FLIGHT,XS(F)
- Try
- S(F);CHECK
- Vars
- R(g);CHECK,P_SPINR(g)::R(I)+S(G),XR(g)
- Refutation
- K(d);P-FLIGHT
- Try
- S(F);CHECK
- Vars
- R(g);CHECK,P_SPINR(g)::R(I)+S(G),XR(g)
- Refutation
- K(d);P-FLIGHT
- Try
- S(F);CHECK
- Vars
- R(g);CHECK,P_SPINR(g)::R(I)+S(G),XR(g)
- Refutation
- K(d);P-FLIGHT
- Try
- S(G);P_PINR(g)
- Threat
- DUALS(6)
- Vars
- R(g);OGATEB::QAR2(K),XR(g)
- Refutation
- R(g);CHECK,N_SPINR(g),XR(I)
- Try
- S(G);P_PINR(g)
- Threat
- S(G)
- Vars
- R(g);OGATEB::QAR2(K),XR(g)
- R(g);OGATEB::R(I),XR(g)
- Refutation
- R(g);CHECK,N_SPINR(g),XR(I)
- Try
- B(H);
- Vars
- R(g);CHECK,P_SPINR(g),XS(F)::R(I)+S(G),XR(g)
- R(g);XP(E)::R(I)+S(G),XR(g)
- R(g);OGATE,P_SPINR(g),XS(G)::R(I),XR(g)
- B(c);N_GUARD,XP(E)::P(A),XP(a)
- P(a);OGATE,XP(A)::R1(C),XP(b)
- R(g);OGATEB::QAR2(K),XR(g)
- B(c);N_GUARD::P(A),XP(a)
- P(a);OGATE::R1(C),XP(b)
- P(e);N_GUARD::R(C),XB(c)
- Refutation
- P(h);
- Try
- R(C);XP(a)
- Threat
- DUALS(2)
- Vars
- R(g);CHECK,P_SPINR(g),XS(F)::R(I)+S(G),XR(g)
- Refutation
- B(c);XR(C)
- Try
- Q(K);
- Vars
- R(g);XP(E)::R(I)+S(G),XR(g)
- R(g);OGATE,P_SPINR(g),XS(G)::R(I),XR(g)
- B(c);N_GUARD,XP(E)::P(A),XP(a)
- P(a);OGATE,XP(A)::R1(C),XP(b)
- R(g);OGATEB::QAR2(K),XR(g)
- B(c);N_GUARD::P(A),XP(a)
- P(a);OGATE::R1(C),XP(b)
- P(e);N_GUARD::R(C),XB(c)
- Refutation
- P(h);
- Try
- Q(K);
- Vars
- R(g);CHECK,OGATE,P_SPINR(g),XS(F)::B(H),XR(g)
- R(g);XP(E)::B(H)+S(F),DCHECK
- R(g);P_SPINR(g),XS(G)::B(H)+S(F),XR(g)
- B(c);N_GUARD,XP(E)::P(A),XP(a)
- P(a);OGATE,XP(A)::R1(C),XP(b)
- R(g);::B(H)+S(F),DCHECK
- B(c);N_GUARD::P(A),XP(a)
- P(a);OGATE::R1(C),XP(b)
- P(e);N_GUARD::R(C),XB(c)
- Refutation
- P(h);
- Try
- Actual
- Q(K);
- Vars
- R(g);CHECK,OGATE,P_SPINR(g),XS(F)::B(H),XR(g)
- R(g);XP(E)::B(H)+S(F),DCHECK
- R(g);P_SPINR(g),XS(G)::B(H)+S(F),XR(g)
- B(c);N_GUARD,XP(E)::P(A),XP(a)
- P(a);OGATE,XP(A)::R1(C),XP(b)
- P(h);N_GUARD::QAR2(K)
- R(g);::B(H)+S(F),DCHECK
- B(c);N_GUARD::P(A),XP(a)
- P(a);OGATE::R1(C),XP(b)
- P(e);N_GUARD::R(C),XB(c)
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