[Event "Manuscrito Anónimo de El Escorial: Alf 55 solucion Esc 20 - Sonja"] [Date "2019.05.29"] [White "Alf 55 solucion Esc 20"] [Black "Sonja"] [Result "0-1"] [FEN "3r2k1/6P1/5PQP/8/p7/P7/2R5/RKBn4 b - - 0 1"] [Variant "From Position"] [ECO "?"] [Opening "?"] [StudyName "Manuscrito Anónimo de El Escorial"] [ChapterName "Alf 55 solucion Esc 20 - Sonja"] [ChapterURL "https://lichess.org/study/UNPT2LTK/pQ5zgcx4"] [Annotator "https://lichess.org/@/LuisAlce"] [FEN "3r2k1/6P1/5PQP/8/p7/P7/2R5/RKBn4 b - - 0 1"] [SetUp "1"] [Orientation "white"] { Problem 55: fols. 38r and 38v (description on fol. 38r and diagram on fol. 38v); 13 pieces: black (at left) plays and wins in three. } 1... Rb8+ 2. Ka2 (2. Rb2 Rxb2+) 2... Rb2+ 3. Rxb2 Nc3# { El negro debe dar jaque siempre ya que el blanco amenaza f7++ o h7++ } 0-1