<div class='user_solution'> <strong>1.f7!</strong><em>(1.e7? Qa4+ 2.Kb8 Rh8+ 3.Kc7 Qc6#)<em><br/> <strong>1...Rh8+ 2.f8Q+ Rxf8+ 3.Rxf8 Kb6 4.Ba6! </strong><em>(4.Rf7? Qa4+ 5.Ba6 (5.Kb8 Qe8#) 5...Qxa6+ 6.Kb8 Qb5 7.Re7 Qc6 8.Ka8<br/> Qh1 9.Rf7 Qa1+ 10.Kb8 Qh8+ 11.Rf8 Qxf8#)<em><br/> <strong>4...Kxa6 5.Rf7!</strong><em>( (5.Rb8? Qd4 6.e7 Qa7#)<em> <br/> <strong>5...Kb6 6.Rd7!</strong><em> with three main lines:</em><br/><br/> <strong>A) 6...Qa4+ 7.Kb8 Qb4 8.e7 Qf4+ 9.Kc8 Qc4+ 10.Kd8!</strong><em> and draw by repetition.<br/> [For example: 10...Qf4 11.e8Q Qb8+ 12.Ke7 Qe5+ 13.Kf7 Qh5+ 14.Kf8 (14.Ke7 Qe5+, =) 14...Qh8+, =];</em><br/><br/> <strong>B) 6...Qh1 7.Rd6+ Kc7</strong><em> (7...Kc5? 8.Ra6! Kb5 9.Ra7! Qe4 10.e7! and White wins)</em><br/> <strong>8.Rd7+ Kb6 9.Rd6+</strong><em> draw by repetition;</em><br/><br/> <strong>C) 6...Qc6 7.Rd6! Qxd6 8.b8Q+ Qxb8+ 9.Kxb8</strong><em> theoretical draw.<br/> Struggle for the promotion of two white pawns;<br/> Bishop sacrifice in order to close the "a" line.</em><br/> </div>