MESON Chess Problem Database

Problem Display
PID: 207749 (qrnNK3/P2Bnp2/Np1k1p2/1Q2p2R/3PR3/1b4b1/8/8 w - - 0 1)

Wright Wood, S (= Wood, SW)

The Observer, 1954

(First published on Sun Oct 3 1954)

qrnNK3/P2Bnp2/Np1k1p2/1Q2p2R/3PR3/1b4b1/8/8

#2

9 + 11

15239 Valois Notebooks 2020

SOLUTION

  • SOUND
  • Sets
    • 1...Qxe4
      • 2.axb8Q#
      • 2.axb8B#
    • 1...Qd5
      • 2.axb8Q#
      • 2.axb8B#
    • 1...Bd1
      • 2.Sxf7#
    • 1...Bc2
      • 2.Sxf7#
    • 1...Ba4
      • 2.Sxf7#
    • 1...Bd5
      • 2.Qb4#
    • 1...Sd5
      • 2.Sxf7#
    • 1...exd4
      • 2.Qb4#
  • Tries
    • 1.Qxb3?
      • threat
        • 2.Sxf7#
      • 1...Qd5
        • 2.axb8Q#
        • 2.axb8B#
      • 1...Sxa7!
    • 1.d5?
      • threat
        • 2.Sxf7#
      • 1...Qxd5
        • 2.axb8Q#
        • 2.axb8B#
      • 1...Bxd5
        • 2.Qb4#
      • 1...Sxa7!
  • Keys
    • 1.Qd3!
      • threat
        • 2.dxe5#
      • 1...Kd5
        • 2.dxe5#
      • 1...exd4
        • 2.Qxg3#
      • 1...Qd5
        • 2.axb8Q#
        • 2.axb8B#
      • 1...Bd5
        • 2.Qa3#
      • 1...Sd5
        • 2.Sxf7#

FEATURES

  • Static
    • TYPE = THREAT
    • CHANGED MATES = 2
    • ADDED MATES = 1
    • REMOVED MATES = 3
  • Sets
    • Q(i);N_GUARD,XR(B)::PXR(j)=Q
    • Q(i);N_GUARD::PXR(j)=Q
    • B(a);N_GUARD::S(H),XP(h)
    • B(a);SBLOCK::QAB(C)
    • S(g);S_CUTB(a)::S(H),XP(h)
    • P(c);XP(A)::QAB(C)
  • Tries
    • Try
      • Q(C);XB(a)
      • Threat
        • S(H),XP(h)
      • Vars
        • Q(i);N_GUARD::PXR(j)=Q
      • Refutation
        • S(k);P_PINS(H),XP(F)
    • Try
      • P(A);
      • Threat
        • S(H),XP(h)
      • Vars
        • Q(i);N_GUARD,XP(A)::PXR(j)=Q
        • B(a);SBLOCK,XP(A)::QAB(C)
      • Refutation
        • S(k);P_PINS(H),XP(F)
  • Actual
    • Q(C);
    • Threat
      • QAR(C)+P(A)DCHECK,XP(c)
    • Vars
      • K(e);P-FLIGHT,P_SPINP(c)::QAR(C)+P(A),XP(c)
      • P(c);OGATEB,P_SPINP(c),XP(A)::QAB(C),XB(b)
      • Q(i);N_GUARD,SBLOCK::PXR(j)=Q
      • B(a);OGATE,SBLOCK::QAB(C)
      • S(g);SBLOCK,S_CUTB(a)::S(H),XP(h)
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