MESON Chess Problem Database

Problem Display
PID: 187484 (8/8/5K2/1NpN1np1/2B1kbPp/1R6/2p5/Q1n5 w - - 0 1)

Byas, Walter

The Observer, 1935

(First published on Sun Sep 22 1935)

8/8/5K2/1NpN1np1/2B1kbPp/1R6/2p5/Q1n5

#2

7 + 8

15239 Valois Notebooks 2019

SOLUTION

  • SOUND
  • Sets
    • 1...Bd2
      • 2.Qe5#
    • 1...Be5+
      • 2.Qxe5#
    • 1...Sa2
      • 2.Qh1#
    • 1...Se2
      • 2.Qh1#
    • 1...Sxb3
      • 2.Qh1#
    • 1...Sd3
      • 2.Qh1#
  • Tries
    • 1.Bd3+?
      • 1...Kxd5
        • 2.Qa8#
      • 1...Sxd3
        • 2.Qh1#
      • 1...Kf3!
  • Keys
    • 1.Be2!
      • threat
        • 2.Bf3#
      • 1...Be5+
        • 2.Qxe5#
      • 1...Kxd5
        • 2.Qa8#
      • 1...Sxe2
        • 2.Qh1#
      • 1...Sxb3
        • 2.Qh1#
      • 1...Be3
        • 2.Qe5#
      • 1...Sd3
        • 2.Qh1#
      • 1...Se3
        • 2.Sdc3#
      • 1...Sd4
        • 2.Sbc3#

FEATURES

  • Static
    • TYPE = THREAT
    • CHANGED MATES = 0
    • ADDED MATES = 4
    • REMOVED MATES = 2
  • Sets
    • B(d);N_GUARD::QAR1(A)
    • B(d);CHECK,N_GUARD::QAR1(A),XB(d)
    • S(a);OGATE::QAB(A)
    • S(a);OGATE,XR(B)::QAB(A)
  • Tries
    • Try
      • B(C);CHECK
      • Vars
        • K(c);S_FLIGHT,XS(F)::QAB(A)
        • S(a);OGATE,XB(C)::QAB(A)
      • Refutation
        • K(c);S_FLIGHT
  • Actual
    • B(C);
    • Threat
      • B(C)
    • Vars
      • B(d);CHECK,N_GUARD::QAR1(A),XB(d)
      • K(c);OGATEB,S_FLIGHT,XS(F)::QAB(A)
      • S(a);OGATE,XB(C)::QAB(A)
      • S(a);OGATE,XR(B)::QAB(A)
      • B(d);N_GUARD::QAR1(A)
      • S(a);OGATE::QAB(A)
      • S(g);SBLOCK::S(F)
      • S(g);SBLOCK::S(E)
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