MESON Chess Problem Database

Problem Display
PID: 188534 (5b2/5rp1/B5n1/2p2n1Q/2N1kppN/7R/8/1KBR4 w - - 0 1)

Langstaff, William A

The Observer, 1937

(First published on Sun Oct 24 1937)

5b2/5rp1/B5n1/2p2n1Q/2N1kppN/7R/8/1KBR4

#2

8 + 9

15239 Valois Notebooks 2019

SOLUTION

  • SOUND
  • Sets
    • 1...Ra7
      • 2.Qxf5#
    • 1...Rb7+
      • 2.Bxb7#
    • 1...Rc7
      • 2.Qxf5#
    • 1...Rd7
      • 2.Qxf5#
    • 1...Re7
      • 2.Qxf5#
    • 1...Be7
      • 2.Bb7#
    • 1...Sg3
      • 2.Qd5#
    • 1...Sd4
      • 2.Sd2#
    • 1...Sfxh4
      • 2.Qd5#
    • 1...Sd6
      • 2.Qd5#
    • 1...Sh6
      • 2.Qd5#
    • 1...Sfe7
      • 2.Sd6#
    • 1...gxh3
      • 2.Qf3#
    • 1...g3
      • 2.Qf3#
  • Tries
    • 1.Qxg4?
      • threat
        • 2.Qf3#
      • 1...Rb7+
        • 2.Bxb7#
      • 1...Sfxh4
        • 2.Re3#
      • 1...Sgxh4
        • 2.Qxf4#
      • 1...Se5
        • 2.Qxf4#
      • 1...Sd4!
  • Keys
    • 1.Sf3!
      • threat
        • 2.Sg5#
      • 1...Rb7+
        • 2.Bxb7#
      • 1...gxf3
        • 2.Qxf3#
      • 1...Sg3
        • 2.Qd5#
      • 1...Be7
        • 2.Bb7#
      • 1...Se3
        • 2.Scd2#
      • 1...Sd4
        • 2.Sfd2#
      • 1...Sfh4
        • 2.Qd5#
      • 1...Sd6
        • 2.Qd5#
      • 1...Sh6
        • 2.Qd5#
      • 1...Sfe7
        • 2.Sd6#

FEATURES

  • Static
    • TYPE = THREAT
    • CHANGED MATES = 0
    • ADDED MATES = 2
    • REMOVED MATES = 6
  • Sets
    • R(g);N_GUARD::QAB1(G),XS(e)
    • R(g);CHECK,N_GUARD::B(H),XR(g)
    • B(i);S_CUTR(g)::B(H)
    • S(e);OGATE::QAB1(G)
    • S(e);SBLOCK::S(E)
    • S(e);OGATE,XS(F)::QAB1(G)
    • S(e);N_GUARD,S_CUTB(i)::S(E)
    • P(c);OGATE,XR(D)::QAB1(G)
    • P(c);OGATE::QAB1(G)
  • Tries
    • Try
      • Q(G);P_PINP(b),XP(c)
      • Threat
        • QAB1(G)
      • Vars
        • R(g);CHECK,N_GUARD::B(H),XR(g)
        • S(e);N_GUARD,XS(F)::R1(D)
        • S(f);N_GUARD,XS(F)::QAR1(G),XP(b)
        • S(f);N_GUARD::QAR1(G),XP(b)
      • Refutation
        • S(e);
  • Actual
    • S(F);
    • Threat
      • S(F)
    • Vars
      • R(g);CHECK,N_GUARD::B(H),XR(g)
      • P(c);OGATE,XS(F)::QAB1(G),XP(c)
      • S(e);OGATE::QAB1(G)
      • B(i);S_CUTR(g)::B(H)
      • S(e);SBLOCK::S(E)
      • S(e);SBLOCK::S(F)
      • S(e);N_GUARD,S_CUTB(i)::S(E)
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