MESON Chess Problem Database

Problem Display
PID: 187142 (2R3BK/8/2P1N1N1/3k1ppp/p6q/B2P1Rn1/1p5b/3Q4 w - - 0 1)

Byas, Walter

The Observer, 1934

(First published on Sun Dec 2 1934)

2R3BK/8/2P1N1N1/3k1ppp/p6q/B2P1Rn1/1p5b/3Q4

#2

10 + 9

15239 Valois Notebooks 2019

SOLUTION

  • SOUND
  • Sets
    • 1...Qd4+
      • 2.Sg7#
  • Tries
    • 1.Sc5+?
      • 1...Kd6
        • 2.Se4#
        • 2.Sb7#
      • 1...Kd4!
    • 1.Sc7+?
      • 1...Kd4
        • 2.Sb5#
      • 1...Kxc6!
    • 1.Qc2?
      • threat
        • 2.Rd8#
        • 2.Qc5#
      • 1...Qd4+
        • 2.Sg7#
      • 1...Qc4
        • 2.Qxc4#
        • 2.dxc4#
      • 1...Qf4
        • 2.Qc5#
      • 1...Bg1
        • 2.Rd8#
      • 1...Sf1
        • 2.Qc5#
      • 1...Sh1
        • 2.Qc5#
      • 1...Se2
        • 2.Qc5#
      • 1...Se4
        • 2.Qc4#
      • 1...g4
        • 2.Qc4#
        • 2.Qc5#
      • 1...Qb4!
    • 1.Qb3+?
      • 1...Qc4
        • 2.Qxc4#
      • 1...axb3!
    • 1.Qe1?
      • threat
        • 2.Se7#
        • 2.Qa5#
        • 2.Qe5#
      • 1...Qd4+
        • 2.Sg7#
      • 1...Qb4
        • 2.Qe5#
      • 1...b1Q
        • 2.Se7#
        • 2.Qe5#
      • 1...b1R
        • 2.Se7#
        • 2.Qe5#
      • 1...Qc4
        • 2.Se7#
        • 2.Qe5#
      • 1...Qe4
        • 2.Qa5#
      • 1...Qf4
        • 2.Se7#
        • 2.Qa5#
      • 1...Bg1
        • 2.Se7#
        • 2.Qe5#
      • 1...Sf1
        • 2.Se7#
        • 2.Qa5#
      • 1...Sh1
        • 2.Se7#
        • 2.Qa5#
      • 1...Se2
        • 2.Qa5#
      • 1...g4
        • 2.Sgf4#
        • 2.Qa5#
        • 2.Qe5#
      • 1...Se4!
  • Keys
    • 1.d4!
      • threat
        • 2.Sxg5#
      • 1...Qxd4+
        • 2.Qxd4#
      • 1...Kc4
        • 2.Sc7#
      • 1...Ke4
        • 2.Sc5#
      • 1...Qe4
        • 2.Sef4#
      • 1...g4
        • 2.Sg5#

FEATURES

  • Static
    • TYPE = THREAT
    • CHANGED MATES = 1
    • ADDED MATES = 4
    • REMOVED MATES = 0
  • Sets
    • Q(e);CHECK,SBLOCK::B(I)+S(F)
  • Tries
    • Try
      • S(F);CHECK
      • Refutation
        • K(f);P-FLIGHT
    • Try
      • S(F);CHECK
      • Vars
        • K(f);P-FLIGHT::S(F)
      • Refutation
        • K(f);S_FLIGHT,XP(E)
    • Try
      • Q(A);
      • Threat
        • DUALS(2)
      • Vars
        • Q(e);CHECK,SBLOCK::B(I)+S(F)
        • Q(e);::QAR1(A)
        • B(b);::R(H)
        • S(c);::QAR1(A)
        • S(c);S_CUTQ(e)::QAB1(A)
      • Refutation
        • Q(e);
    • Try
      • Q(A);CHECK
      • Vars
        • Q(e);N_GUARD,P_SPINQ(e)::QAB1(A),XQ(e)
      • Refutation
        • P(d);XQ(A)
    • Try
      • Q(A);
      • Threat
        • DUALS(3)
      • Vars
        • Q(e);CHECK,SBLOCK::B(I)+S(F)
        • Q(e);::QAR1(A)
        • Q(e);::QAR(A)
        • S(c);::QAR(A)
      • Refutation
        • S(c);
  • Actual
    • P(C);
    • Threat
      • B(I)+S(F),XP(h)
    • Vars
      • Q(e);CHECK,OGATE,P_SPINQ(e),XP(C)::QAR1(A),XQ(e)
      • K(f);S_FLIGHT::B(I)+S(F)
      • K(f);S_FLIGHT::S(F)
      • Q(e);SBLOCK::B(I)+S(F),DCHECK
      • P(h);::B(I)+S(F)
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