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Fen: RuyLopez - r1bqkbnr/pppp1ppp/2n5/1B2p3/4P3/5N2/PPPP1PPP/RNBQK2R
Fen: Najdorf - rnb1kb1r/1p3ppp/pq1ppn2/6B1/3NPP2/2N5/PPP3PP/R2QKB1R
Fen: Mate - 2r2rk1/pbq2ppp/1pp1n3/3nN3/P1BPN1Q1/R7/1P3PPP/4R1K1
Fen: Stein - Portisch, Stockholm 1962- r4r1k/2q2ppp/1np1b3/p1b1pNB1/2B1P3/8/PPP1Q1PP/3R1R1K
1.Nxf6+ Qxf6 2.Qf8# r1bq2k1/ppp2r1p/2np1pNQ/2bNpp2/2B1P3/3P4/PPP2PPP/R3K2R w KQ - 0 1
1.Qxf6+ gxf6 2.Bxf6# r1bk3r/1pp2ppp/pb1p1n2/n2P4/B3P1q1/2Q2N2/PB3PPP/RN3RK1 w - - 0 1
1.Nh5+ Ke8 2.Nf6# r2q1k1r/ppp1n1Np/1bnpB2B/8/1P1pb1P1/2P4P/P4P2/R2Q1RK1 w - - 0 1
1.Qxf7+ Rxf7 2.Re8# r1b2rk1/ppp2p1p/1b1p1B2/5q1Q/2Bp4/2P5/PP3PPP/R3R1K1 w - - 0 1
1.Nxf7+ Bxf7 2.Bxe7# 1rqk3r/p1p1pppp/2Q1b3/3pN3/3P4/B7/P4PPP/b3R1K1 w - - 0 1
1.Qxf8+ Nxf8 2.Re8# r2k1b1Q/pppn3p/3p4/1B5n/5pb1/5N2/PPPP1qPP/RNBKR3 w - - 0 1
1.Qb3+ Kd4 2.Qd3# r4r2/pQ3ppp/2np4/2bk4/5P2/6P1/PPP5/R1B1KB1q w Q - 0 1
1.Qxh6+ gxh6 2.Be5# rnbqr2k/ppppn1p1/1b5p/6NQ/2BPPB2/8/PPP3PP/RN3K1R w - - 0 1
1.Qxh8+ Nxh8 ( 1...Nf8 2.Rxf8# ( 2.Qxf8# ) ) 2.Rf8# r1bk3b/1pppq3/2n3n1/1p2P1BQ/3P4/8/PPP3P1/5RK1 w - - 0 1
1.Qf6+ Nxf6 2.Be7# r1bk2nr/p2p1pNp/n2B4/1p1NP2P/6P1/3P1Q2/P1P1K3/q5b1 w - - 0 1
1.Ng6+ hxg6 2.Qxh8# rnb2k1r/ppp1qBpp/8/4N2Q/8/2n3b1/PPPP2K1/R1B2R2 w - - 0 1
1.Bxf7+ Qxf7 ( 1...Kxf7 2.Qg6# ) 2.Qd8# r1b1kbnr/pp2qp2/1np4p/4P3/2B2BpN/2NQ1pP1/PPP4P/2KR3R w kq - 0 1
1.Qe8+ Rxe8 2.Nf7# rnbk3r/ppppb2p/3N1n2/7Q/4P3/2N5/PPPP3P/R1B1KB1q w Q - 0 1
1.Be6+ Kxe6 2.Qf7# r1b2Qnr/p1pk3p/1pnp4/6q1/2BPP3/8/PPP3PP/RN3RK1 w - - 0 1
1.Rh5+ Bxh5 2.Nf5# r4b1r/ppp1qb2/2np3p/5R2/3PP2k/4B1NP/PPP3K1/8 w - - 0 1
1.Qf5+ Nxf5 2.e6# r1b3nr/ppqk1Bbp/2pp4/4P1B1/3n4/3P4/PPP2QPP/R4RK1 w - - 0 1
1.Qe4+ Kxe4 2.Nc3# rn5r/pp1b2b1/1q1p3p/3nk1p1/3p4/3Q2P1/PPP1NR2/4R1K1 w - - 0 1
1.Ne6+ Bxe6 2.Bh6# r2q1k1r/ppp1bB1p/2np4/6N1/3PP1bP/8/PPP5/RNB2RK1 w - - 0 1

This is not a chess playing program nor does it have any grasp of how chess pieces move.
Simply pick up and piece with a mouse down and move it to any other square.
Move a piece off the board to delete it.
Replace a lost piece by dragging one from the Piece Toolbox.

After 7. Bc1-g5 Qd8xd4 it seems White is bust as forced play follows, it is only after 12. o-o-o (castling)
that White even appears to be in the game.
Black chases another pawn with the Queen as the White King moves to a safer column
16. g2-g4 f7-f5 - Over confident, maybe but clearly trying to activate white squared Bishop.
18. Bd3-c4+ leads to 19. e4-e5 and 21. e5-e6 - a central isolated passed pawn almost has the power of a piece
By 21. Black has made five moves with the Queen. White just the one.
24. h4-h5 g6xh5 - Black really cracks under the strain, none of his pieces are near his King (e6:c7,g7 fork)
26. Ng5-f7+ and it really is all over, (mate in ten!?),
the Rook sacrifice is just the cherry on top, as a fork will always recover that piece.

7.	Bc1-g5	...	r1bqkb1r/pp2pppp/2p2n2/6B1/3P4/3B4/PPP2PPP/R2QK1NR
12.	o-o-o	...	r1b1kb1r/pp3ppp/2p1p3/4q3/8/2PBP3/PP2Q1PP/2KR2NR
17.	g2-g4	...	r1b2rk1/pp3ppp/1qp1p3/2b5/4P1P1/2PB1N2/PP2Q2P/1K1R3R
21.	...	g7-g6	r1b1r2k/pp5p/1qp3p1/2b1PpN1/2B5/2P5/PP2Q2P/1K1R3R
26.	...	Re8-e7	r1b4k/2q1r2p/2p1P3/ppb2pNR/8/1BP5/PP2Q3/1K1R4