MESON Chess Problem Database
Problem Display
PID: 195805 (8/5Q2/3P2p1/1P2p1N1/3pP1B1/4kp2/2PnNRp1/2B1n1Kb w - - 0 1)
Stewart, John
The Observer, 1942
(First published on Sun Feb 22 1942)
#2
11 + 9
| 15239 | Valois Notebooks | 2019 |
SOLUTION
- SOUND
- Sets
- 1...Sxc2
- 2.Qxf3#
- 1...Sd3
- 2.Qxf3#
- 1...fxe2
- 2.Rxe2#
- 1...d3
- 2.Qa7#
- 1...Sxc2
- Tries
- 1.Sg3?
- threat
- 2.Bxd2#
- 1...Sxc2
- 2.Rxf3#
- 2.Qxf3#
- 1...d3!
- threat
- 1.Sf4?
- threat
- 2.Sd5#
- 2.Bxd2#
- 1...Sxc2
- 2.Bxd2#
- 2.Rxf3#
- 1...exf4
- 2.Bxd2#
- 1...d3!
- threat
- 1.Bh3?
- 1...Sxc2
- 2.Qxf3#
- 1...d3
- 2.Qa7#
- 1...Sd3
- 2.Qxf3#
- 1...fxe2!
- 1...Sxc2
- 1.Bh5?
- 1...Sxc2
- 2.Qxf3#
- 1...fxe2
- 2.Rxe2#
- 1...d3
- 2.Qa7#
- 1...Sd3
- 2.Qxf3#
- 1...gxh5!
- 1...Sxc2
- 1.Be6?
- 1...Sxc2
- 2.Qxf3#
- 1...d3
- 2.Qa7#
- 1...Sd3
- 2.Qxf3#
- 1...fxe2!
- 1...Sxc2
- 1.Bc8?
- 1...Sxc2
- 2.Qxf3#
- 1...d3
- 2.Qa7#
- 1...Sd3
- 2.Qxf3#
- 1...fxe2!
- 1...Sxc2
- 1.Rxg2?
- 1...f2+
- 2.Qxf2#
- 1...Sxc2
- 2.Qxf3#
- 1...Sxg2
- 2.Qxf3#
- 1...fxe2
- 2.Rxe2#
- 2.Qf2#
- 1...fxg2
- 2.Qf2#
- 1...d3
- 2.Qa7#
- 1...Sd3
- 2.Qxf3#
- 1...Bxg2!
- 1...f2+
- 1.Rxf3+?
- 1...Sxf3+
- 2.Qxf3#
- 1...Kxe2!
- 1...Sxf3+
- 1.Qb3+?
- 1...Sd3
- 2.Qxd3#
- 1...d3!
- 1...Sd3
- 1.Qf6?
- 1...Sxc2
- 2.Qxf3#
- 1...fxe2
- 2.Rxe2#
- 1...Sd3
- 2.Qxf3#
- 1...d3!
- 1...Sxc2
- 1.Qf8?
- 1...Sxc2
- 2.Qxf3#
- 1...fxe2
- 2.Rxe2#
- 1...Sd3
- 2.Qxf3#
- 1...d3!
- 1...Sxc2
- 1.b6?
- 1...Sxc2
- 2.Qxf3#
- 1...fxe2
- 2.Rxe2#
- 1...Sd3
- 2.Qxf3#
- 1...d3!
- 1...Sxc2
- 1.d7?
- 1...Sxc2
- 2.Qxf3#
- 1...fxe2
- 2.Rxe2#
- 1...Sd3
- 2.Qxf3#
- 1...d3!
- 1...Sxc2
- 1.Sg3?
- Keys
- 1.Qc4!
- 1...Sxc2
- 2.Rxf3#
- 1...fxe2
- 2.Qxe2#
- 1...d3
- 2.Qc5#
- 1...Sd3
- 2.Qxd3#
- 1...Sxc2
- 1.Qc4!
FEATURES
- Static
- TYPE = MUTATE
- CHANGED MATES = 4
- ADDED MATES = 0
- REMOVED MATES = 0
- Sets
- S(a);N_GUARD,XP(C)::QAR1(K),XP(f)
- S(a);N_GUARD::QAR1(K),XP(f)
- P(f);OGATE,XS(D)::R1(E),XP(f)
- P(g);OGATEB::QAB(K)
- Tries
- Try
- S(D);
- Threat
- B(A),XS(c)
- Refutation
- P(g);
- Try
- S(D);
- Threat
- DUALS(2)
- Vars
- P(h);XS(D)::B(A),XS(c)
- Refutation
- P(g);
- Try
- B(G);
- Vars
- S(a);N_GUARD,XP(C)::QAR1(K),XP(f)
- P(g);OGATEB::QAB(K)
- S(a);N_GUARD::QAR1(K),XP(f)
- Refutation
- P(f);XS(D)
- Try
- B(G);
- Vars
- S(a);N_GUARD,XP(C)::QAR1(K),XP(f)
- P(f);OGATE,XS(D)::R1(E),XP(f)
- P(g);OGATEB::QAB(K)
- S(a);N_GUARD::QAR1(K),XP(f)
- Refutation
- P(i);XB(G)
- Try
- B(G);
- Vars
- S(a);N_GUARD,XP(C)::QAR1(K),XP(f)
- P(g);OGATEB::QAB(K)
- S(a);N_GUARD::QAR1(K),XP(f)
- Refutation
- P(f);XS(D)
- Try
- B(G);
- Vars
- S(a);N_GUARD,XP(C)::QAR1(K),XP(f)
- P(g);OGATEB::QAB(K)
- S(a);N_GUARD::QAR1(K),XP(f)
- Refutation
- P(f);XS(D)
- Try
- R(E);XP(d)
- Vars
- P(f);CHECK,OGATE::QAB1(K),XP(f)
- S(a);N_GUARD,XP(C)::QAR1(K),XP(f)
- S(a);N_GUARD,XR(E)::QAR1(K),XP(f)
- P(f);OGATE,XR(E)::QAB1(K)
- P(g);OGATEB::QAB(K)
- S(a);N_GUARD::QAR1(K),XP(f)
- Refutation
- B(b);XR(E)
- Try
- R(E);CHECK,XP(f)
- Vars
- S(a);CHECK,OGATE,XR(E)::QAR1(K),XS(a)
- Refutation
- K(e);N_SPINS(c),P-FLIGHT,XS(D)
- Try
- Q(K);CHECK
- Vars
- S(a);N_GUARD::QAR1(K),XS(a)
- Refutation
- P(g);P_SPINP(g)
- Try
- Q(K);
- Vars
- S(a);N_GUARD,XP(C)::QAR1(K),XP(f)
- P(f);OGATE,XS(D)::R1(E),XP(f)
- S(a);N_GUARD::QAR1(K),XP(f)
- Refutation
- P(g);
- Try
- Q(K);
- Vars
- S(a);N_GUARD,XP(C)::QAR1(K),XP(f)
- P(f);OGATE,XS(D)::R1(E),XP(f)
- S(a);N_GUARD::QAR1(K),XP(f)
- Refutation
- P(g);
- Try
- P(H);
- Vars
- S(a);N_GUARD,XP(C)::QAR1(K),XP(f)
- P(f);OGATE,XS(D)::R1(E),XP(f)
- S(a);N_GUARD::QAR1(K),XP(f)
- Refutation
- P(g);
- Try
- P(J);
- Vars
- S(a);N_GUARD,XP(C)::QAR1(K),XP(f)
- P(f);OGATE,XS(D)::R1(E),XP(f)
- S(a);N_GUARD::QAR1(K),XP(f)
- Refutation
- P(g);
- Try
- Actual
- Q(K);
- Vars
- S(a);N_GUARD,XP(C)::R1(E),XP(f)
- P(f);OGATE,XS(D)::QAR1(K),XP(f)
- P(g);OGATEB::QAB(K)
- S(a);N_GUARD::QAR1(K),XS(a)
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