@InspectorBaboon@ImShahinyan There's another solution
B.a3: If the king moves C2, move Q.d3 checkmate, and if the king moves in square E1, move B.b4 checkmate.
@Mark_Wylie001@ImShahinyan Oh, right. Let's think again.ย
Ba3: If the king moves C2, move Qd3 checkmate, and if the king moves in square E1, move Bb4 checkmate.