rnbqkb1r/pppp1ppp/5n2/4p3/4P3/5N2/PPPP1PPP/RNBQKB1R w KQkq - 2 3 ; C42 Petrov's Defense
rnbqkb1r/pppp1ppp/5n2/4N3/4P3/8/PPPP1PPP/RNBQKB1R b KQkq - 0 3 ; C42 Petrov's Defense
rnbqkb1r/ppp2ppp/3p1n2/4N3/4P3/8/PPPP1PPP/RNBQKB1R w KQkq - 0 4 ; C42 Petrov's Defense
rnbqkb1r/ppp2ppp/3p1n2/8/4P3/5N2/PPPP1PPP/RNBQKB1R b KQkq - 1 4 ; C42 Petrov's Defense
rnbqkb1r/ppp2ppp/3p4/8/4n3/5N2/PPPP1PPP/RNBQKB1R w KQkq - 0 5 ; C42 Petrov's Defense
rnbqkb1r/ppp2ppp/3p4/8/3Pn3/5N2/PPP2PPP/RNBQKB1R b KQkq - 0 5 ; C42 Petrov's Defense: Classical Attack
r2qk2r/ppp1b1pp/2n5/3p1p2/3Pn1b1/2PB1N2/PP1N1PPP/R1BQR1K1 b kq - 1 10 ; C42 Petrov's Defense: Classical Attack, Berger Variation
r1bqk2r/ppp1bppp/2n5/3p4/3Pn3/3B1N2/PPP2PPP/RNBQR1K1 b kq - 5 8 ; C42 Petrov's Defense: Classical Attack, Chigorin Variation
r1bqk2r/ppp1bppp/8/3P4/1n1Pn3/3B1N2/PP3PPP/RNBQ1RK1 b kq - 0 9 ; C42 Petrov's Defense: Classical Attack, Chigorin Variation, Browne Attack
r1bqk2r/ppp1bppp/8/3p4/1nPPn3/5N2/PP2BPPP/RNBQ1RK1 b kq - 2 9 ; C42 Petrov's Defense: Classical Attack, Chigorin Variation, Main Line
rnbqkb1r/ppp2ppp/3p1n2/8/3P4/5N2/PPP2PPP/RNBQKB1R w KQkq - 1 6 ; C42 Petrov's Defense: Classical Attack, Closed Variation
r1bqk2r/ppp1bppp/2n5/3p4/2PPn3/3B1N2/PP3PPP/RNBQ1RK1 b kq - 0 8 ; C42 Petrov's Defense: Classical Attack, Jaenisch Variation
r2qk2r/ppp1b1pp/2n5/3p1p2/2PPn1b1/3B1N2/PP3PPP/RNBQR1K1 b kq - 0 10 ; C42 Petrov's Defense: Classical Attack, Krause Variation
rn1q1rk1/ppp3pp/8/3P1p2/3Pn1b1/3B1N2/PP3PPb/RNBQR1K1 w - - 0 11 ; C42 Petrov's Defense: Classical Attack, Marshall Trap
rnbqk2r/ppp2ppp/3b4/3p4/3Pn3/3B1N2/PPP2PPP/RNBQK2R w KQkq - 2 7 ; C42 Petrov's Defense: Classical Attack, Marshall Variation
rn1q1rk1/pp3ppp/2pb4/3p4/2PPn1b1/3B1N2/PP3PPP/RNBQR1K1 w - - 2 10 ; C42 Petrov's Defense: Classical Attack, Marshall Variation, Chinese Gambit
r2qk2r/ppp3pp/2n5/3p1p2/2PPn1bb/3B1N2/PP3PPP/RNBQR1K1 w kq - 1 11 ; C42 Petrov's Defense: Classical Attack, Maróczy Variation
rnbq1rk1/ppp1bppp/8/3p4/3Pn3/3B1N2/PPP2PPP/RNBQ1RK1 w - - 4 8 ; C42 Petrov's Defense: Classical Attack, Mason Variation
r1bqkb1r/ppp2ppp/2n5/3p4/3Pn3/3B1N2/PPP2PPP/RNBQK2R w KQkq - 2 7 ; C42 Petrov's Defense: Classical Attack, Mason-Showalter Variation
rnbq1rk1/pp3ppp/2pb4/3p4/2PPn3/3B1N2/PP3PPP/RNBQ1RK1 w - - 0 9 ; C42 Petrov's Defense: Classical Attack, Staunton Variation
rn1q1rk1/ppp2ppp/3b4/3p4/2PPn1b1/3B1N2/PP3PPP/RNBQ1RK1 w - - 1 9 ; C42 Petrov's Defense: Classical Attack, Tarrasch Variation
rnbqkb1r/ppp2Npp/3p1n2/8/4P3/8/PPPP1PPP/RNBQKB1R b KQkq - 0 4 ; C42 Petrov's Defense: Cochrane Gambit
rnbq1b1r/ppp2kpp/3p1n2/8/2B1P3/8/PPPP1PPP/RNBQK2R b KQ - 1 5 ; C42 Petrov's Defense: Cochrane Gambit, Bishop Check Line
rnbq1b1r/ppp2kpp/3p1n2/8/3PP3/8/PPP2PPP/RNBQKB1R b KQ - 0 5 ; C42 Petrov's Defense: Cochrane Gambit, Center Variation
rnbqkb1r/ppp2ppp/3p4/8/4n3/5N2/PPPPQPPP/RNB1KB1R b KQkq - 1 5 ; C42 Petrov's Defense: Cozio Attack
rnbqkb1r/pppp1ppp/8/4N3/4n3/8/PPPP1PPP/RNBQKB1R w KQkq - 0 4 ; C42 Petrov's Defense: Damiano Variation
rnb1kb1r/ppppqppp/8/4N3/4n3/8/PPPPQPPP/RNB1KB1R w KQkq - 2 5 ; C42 Petrov's Defense: Damiano Variation, Kholmov Gambit
rnbqkb1r/ppp2ppp/3p4/8/4n3/3P1N2/PPP2PPP/RNBQKB1R b KQkq - 0 5 ; C42 Petrov's Defense: French Attack
rnbqkb1r/pppp1ppp/5n2/4p3/2B1P3/5N2/PPPP1PPP/RNBQK2R b KQkq - 3 3 ; C42 Petrov's Defense: Italian Variation
rnbqkb1r/ppp2ppp/3p1n2/8/4P3/3N4/PPPP1PPP/RNBQKB1R b KQkq - 1 4 ; C42 Petrov's Defense: Karklins-Martinovsky Variation
rnbqkb1r/ppp2ppp/3p4/8/2P1n3/5N2/PP1P1PPP/RNBQKB1R b KQkq - 0 5 ; C42 Petrov's Defense: Kaufmann Attack
rnbqkb1r/ppp2ppp/3p4/8/4n3/3B1N2/PPPP1PPP/RNBQK2R b KQkq - 1 5 ; C42 Petrov's Defense: Millennium Attack
r1bqkb1r/pppp1ppp/2n2n2/4p3/3PP3/5N2/PPP1QPPP/RNB1KB1R b KQkq - 0 4 ; C42 Petrov's Defense: Moody Gambit
rnbqkb1r/ppp2ppp/3p4/8/4n3/2N2N2/PPPP1PPP/R1BQKB1R b KQkq - 1 5 ; C42 Petrov's Defense: Nimzowitsch Attack
rnbqkb1r/ppp2ppp/3p1n2/8/2N1P3/8/PPPP1PPP/RNBQKB1R b KQkq - 1 4 ; C42 Petrov's Defense: Paulsen Attack
r1bqkb1r/pppp1ppp/2n2n2/4N3/4P3/8/PPPP1PPP/RNBQKB1R w KQkq - 1 4 ; C42 Petrov's Defense: Stafford Gambit
r1bqkb1r/ppp2ppp/2p2n2/8/4P3/8/PPPP1PPP/RNBQKB1R w KQkq - 0 5 ; C42 Petrov's Defense: Stafford Gambit Accepted
r1bqk2r/ppp2ppp/2p2n2/2b5/4P3/2N5/PPPP1PPP/R1BQKB1R w KQkq - 2 6 ; C42 Petrov's Defense: Stafford Gambit Accepted
r1bqk2r/ppp2ppp/2p2n2/2b5/4P3/3P4/PPP2PPP/RNBQKB1R w KQkq - 1 6 ; C42 Petrov's Defense: Stafford Gambit Accepted
rnbqkb1r/pppp1ppp/5n2/4p3/4P3/2N2N2/PPPP1PPP/R1BQKB1R b KQkq - 3 3 ; C42 Petrov's Defense: Three Knights Game
rnbqkb1r/pppp1ppp/5n2/4p3/3PP3/5N2/PPP2PPP/RNBQKB1R b KQkq - 0 3 ; C43 Petrov's Defense: Modern Attack
rnbqkb1r/pppp1ppp/5n2/8/3pP3/5N2/PPP2PPP/RNBQKB1R w KQkq - 0 4 ; C43 Petrov's Defense: Modern Attack
r1bqkb1r/pppp1ppp/2n5/2n1P3/3N4/8/PPP1QPPP/RNB1KB1R w KQkq - 1 7 ; C43 Petrov's Defense: Modern Attack, Bardeleben Variation
rnbqkb1r/pppp1ppp/8/4P3/3Qn3/5N2/PPP2PPP/RNB1KB1R b KQkq - 0 5 ; C43 Petrov's Defense: Modern Attack, Center Attack
rnbqkb1r/pppp1ppp/8/4p3/3Pn3/3B1N2/PPP2PPP/RNBQK2R b KQkq - 1 4 ; C43 Petrov's Defense: Modern Attack, Center Variation
r1bqkb1r/pppp1ppp/2n5/4p3/3Pn3/3B1N2/PPP2PPP/RNBQK2R w KQkq - 2 5 ; C43 Petrov's Defense: Modern Attack, Murrey Variation
rnbqkb1r/pppp1ppp/8/4P3/3pn3/5N2/PPP1QPPP/RNB1KB1R b KQkq - 2 5 ; C43 Petrov's Defense: Modern Attack, Steinitz Variation
rnbqkb1r/ppp2ppp/5n2/3pp3/3PP3/5N2/PPP2PPP/RNBQKB1R w KQkq - 0 4 ; C43 Petrov's Defense: Modern Attack, Symmetrical Variation
rnbqkb1r/pppp1ppp/8/1B2P3/3pn3/5N2/PPP2PPP/RNBQK2R b KQkq - 2 5 ; C43 Petrov's Defense: Modern Attack, Tal Gambit
rnbq1rk1/ppp2ppp/8/3pb3/2PPn3/3B4/PP3PPP/RNBQ1RK1 w - - 0 8 ; C43 Petrov's Defense: Modern Attack, Trifunovic Variation