FIND THE MOVE
   

DIAGRAM 1




Position from the game Costa - Coha (FSI 2 cat. Latina, 1983)

White has the move and wins


tip

solution
       

DIAGRAM 2



Position from the game Costa - Akadegawa (ICCF EM-H-021, 2000)

White has the move and wins

tip

solution
   
DIAGRAM 3



Position from the game Costa - Oppici
(ASIGC 1=D-240, 1985)
White has the move and achieves a clear advantage

tip

 
DIAGRAM 4



Position from the game 
Costa - Adamczyk (TGT 5-12, 1999)
White has the move and wins

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DIAGRAM 5White has the move and achieves a clear advantage



Position from the game 
Costa - Buczinsky (ICCF EM-M-191, 2002)
White has the move and achieves a clear advantage

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 TIPS
1 Black seems to defend the critical h7 square but his position is cramped. White has to proceed vigorously, even with sacrifices.  
White's idea is based on a final Queen's sacrifice one move before the check mate.
2 Black's Queen, in spite of the check delivered, is in a vulnerable position and can be captured with a combination.
3 White has to ignore the threat of the Bishop in a6 continuing his attack towards the enemy's King.
4 If Black's Knight is removed from f5, White can leverage on Black's weak dark squares, especially in front of Black's King.
5
The natural sequence 1.Bxf6  Bxf6 2.Rxh7 Nxh7 3.Qxh7+ Kf8 4.Nd2 Qf7 5.Ne4 Ke7 6.Qg6 Qxg6 7.fxg6 Rh8 is in Black's favor. However White can first play an apparently innocuous intermediate move after which the same sequencegives  advantage to White.
 Back to diagram 5
 
 
 
 
 
 
 
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