This is aimed at the White King’s pawn, which is deprived of its natural support by the QKt. In this position Black does well to attack White’s KP rather than to defend his own, because an open King’s file can only benefit him. Being able to castle, he can occupy the file with his Rook before White has time to bring his King into safety.
8. KtxP
It would have been better to protect the pawn by Q-K2 or P-Q3.
8. … Castles!
Diag. 100
The beginning of a brilliant attack. Whether White exchanges the Bishop or the Knight, he is overwhelmed.
9. KtxKt
After 9. BxKt, PxB; 10. KtxP, Q-K1 wins; 10. P-Q4 would also lose because Black gains two pawns after KtxP; 11. O-O, KtxP. It is interesting to note how speedily the weakness at White’s QB3 is brought to book.
9. … PxKt 10. BxP KtxP!!