MESON Chess Problem Database

Problem Display
PID: 27311 (3k4/N3n1R1/8/8/8/2Q5/K7/8 w - - 0 1)

Lebeck, Donald

Mate in Two!! (Lebeck), 1992

3k4/N3n1R1/8/8/8/2Q5/K7/8

#2

4 + 2

SOLUTION

  • SOUND
  • Sets
    • 1...Sd5
      • 2.Qc8#
    • 1...Sf5
      • 2.Qc8#
    • 1...Sg6
      • 2.Qc8#
    • 1...Sc8
      • 2.Qxc8#
    • 1...Sg8
      • 2.Qc8#
  • Tries
    • 1.Qb4?
      • threat
        • 2.Qxe7#
      • 1...Kd7
        • 2.Qxe7#
      • 1...Ke8
        • 2.Qxe7#
      • 1...Sd5
        • 2.Qf8#
        • 2.Qb8#
      • 1...Sf5
        • 2.Qf8#
        • 2.Qb8#
      • 1...Sc6
        • 2.Qf8#
      • 1...Sg6
        • 2.Qb8#
      • 1...Sc8
        • 2.Qf8#
      • 1...Sg8
        • 2.Qf8#
        • 2.Qb8#
      • 1...Kc7!
    • 1.Qe5?
      • threat
        • 2.Qxe7#
      • 1...Kd7
        • 2.Qxe7#
      • 1...Ke8
        • 2.Qxe7#
      • 1...Sd5
        • 2.Qb8#
      • 1...Sf5
        • 2.Qb8#
      • 1...Sg6
        • 2.Qb8#
      • 1...Sc8
        • 2.Sc6#
      • 1...Sg8
        • 2.Qb8#
      • 1...Sc6!
    • 1.Qf6?
      • threat
        • 2.Qxe7#
      • 1...Kd7
        • 2.Qxe7#
      • 1...Ke8
        • 2.Qxe7#
      • 1...Kc7!
    • 1.Qc6?
      • 1...Sd5
        • 2.Qd7#
        • 2.Qa8#
        • 2.Qc8#
      • 1...Sf5
        • 2.Qd7#
        • 2.Qa8#
        • 2.Qc8#
      • 1...Sg6
        • 2.Qd7#
        • 2.Qa8#
        • 2.Qc8#
      • 1...Sc8
        • 2.Qd7#
        • 2.Qxc8#
      • 1...Sg8
        • 2.Qd7#
        • 2.Qa8#
        • 2.Qc8#
      • 1...Sxc6!
    • 1.Qc7+?
      • 1...Ke8
        • 2.Qxe7#
      • 1...Kxc7!
  • Keys
    • 1.Qc5!
      • threat
        • 2.Qxe7#
      • 1...Kd7
        • 2.Qxe7#
      • 1...Ke8
        • 2.Qxe7#
      • 1...Sd5
        • 2.Qf8#
        • 2.Qc8#
      • 1...Sf5
        • 2.Qf8#
        • 2.Qc8#
      • 1...Sc6
        • 2.Qf8#
      • 1...Sg6
        • 2.Qc8#
      • 1...Sc8
        • 2.Qf8#
        • 2.Qxc8#
      • 1...Sg8
        • 2.Qf8#
        • 2.Qc8#

FEATURES

  • Static
    • TYPE = THREAT
    • CHANGED MATES = 0
    • ADDED MATES = 3
    • REMOVED MATES = 4
  • Sets
    • S(a);N_GUARD::QAR1(B)
    • S(a);N_GUARD::QAR1(B),XS(a)
  • Tries
    • Try
      • Q(B);
      • Threat
        • QAB1(B),XS(a)
      • Vars
        • K(b);P-FLIGHT,P_SPINS(a)::QAR1(B),XS(a)
        • K(b);P-FLIGHT::QAR1(B),XS(a)
        • S(a);OGATE::QAR2(B)
        • S(a);N_GUARD::QAR2(B)
      • Refutation
        • K(b);P_SPINS(a),S_FLIGHT
    • Try
      • Q(B);
      • Threat
        • QAB1(B),XS(a)
      • Vars
        • K(b);P-FLIGHT,P_SPINS(a)::QAR1(B),XS(a)
        • S(a);N_GUARD::QAR2(B)
        • S(a);N_GUARD,SBLOCK::S(C)
      • Refutation
        • S(a);
    • Try
      • Q(B);P_PINS(a)
      • Threat
        • QAB1(B),XS(a)
      • Vars
        • K(b);P-FLIGHT::QAR1(B),XS(a)
        • K(b);N_SPINS(a),P-FLIGHT::QAR1(B),XS(a)
      • Refutation
        • K(b);S_FLIGHT
    • Try
      • Q(B);
      • Refutation
        • S(a);XQ(B)
    • Try
      • Q(B);CHECK
      • Vars
        • K(b);P-FLIGHT::QAR1(B),XS(a)
      • Refutation
        • K(b);P_SPINS(a),S_FLIGHT,XQ(B)
  • Actual
    • Q(B);
    • Threat
      • QAB1(B),XS(a)
    • Vars
      • K(b);P-FLIGHT,P_SPINS(a)::QAR1(B),XS(a)
      • K(b);P-FLIGHT::QAR1(B),XS(a)
      • S(a);OGATE::QAR2(B)
      • S(a);N_GUARD::QAR1(B)
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