White's QBPawn to QB4(c4) attacked Black's queen so as to
gain a tempo by its forced moving again. Black moves his Queen under attack on Q4(d5)
to K5(e4) with check, for a slight advantage.
White Black
1. P-K4 P-QB4
2. P-QKt4 PxP
3. B-Kt2 P-Q4
4. PxP QxP
5. P-QB4 Q-K5 ch