Chess Board
[ECO code B20]
SICILIAN DEFENCE
Sicilian Centre Game
White's KB4(f4) Pawn moves straight on to KB5(f5) to further attack Black's knight now on KKt3(g6).
Black's beset Knight returns to K4(e5) with the loss of two tempi. Tending to slight White advantage.
	White   Black
 1.	P-K4    P-QB4
 2.	P-Q4!?  Kt-QB3
 3.	P-Q5    Kt-K4
 4.	P-KB4   Kt-Kt3
 5.	P-B5    Kt-K4
Example ends: Undo or Jump or Clear