1 2
black is threatening to capture white's Queen from # 1 - black moves the Rook so that if black captures
note that black is also concerned about white's
pawn on e4 - and it's threat of pushing to e5
(with a fork) and white's dominance of the
a1-h8 diagonal
Q) what is black's most active defence the Queen, then white captures black's Queen
3 4
5 6
and after 27 …Rxe4 black has gained material (pawn)
as well as reduced white's dominance of the centre
 - drawback being white's invasion of the 7th ranks