Chess Board
[ECO code C23]
BISHOP'S OPENING - Calabrian C-G.
Jaenisch Variation
Black set his QP on Q3(d6), defending his KP and freeing his QB to defend his KBP.
White develops his King's Knight to KB3(f3) for advantage, e.g. (best) 5..BPxP, 6.QPxP..B-Kt5, 7.PxP.
	White	Black
 1.	P-K4	P-K4
 2.	B-B4	P-KB4?!
 3.	P-Q3	Kt-KB3
 4.	P-B4	P-Q3
 5.	Kt-KB3
Example ends: Undo or Jump or Clear