Chess Board
[ECO code A40]
POLISH DEFENCE
White develops his King's Knight to KB3(f3), blocks to prevent 4..BxKtP, 5..BxR, doubles his QP support and enables castling.
Black pushes his Queen's Bishop's Pawn out to QB3(c6) to attack and dislodge White's light bishop, and supports 5..P-Q4, 6..Kt-Q2 with equality.
	White	Black
 1.	P-Q4	P-QKt4
 2.	P-K4!	B-Kt2
 3.	BxP	BxP
 4.	Kt-KB3	P-QB3
Example ends: Undo or Jump or Clear