a)diagram
1...EAb3-g6 2.Ke3-f4 + Kc3-d4 3.HAf7-f5 Me8-g5 4.Rf3-g3 Mg5-e6 #
1...Me8-f2 2.HAf7-c4 EAb3-c2 3.Rf3-f4 EAc2-f1 4.HAc4-e2 Mf2-d1 #
b) bRf3-->g3
1...EAb3-c2 2.Rg3-g2 EAc2-g1 3.Rg2-e2 Me8-f2 4.HAf7-f3 EAg1-g3 #
1...Kc3-c4 2.Ke3-e4 EAb3-g2 3.Rg3-e3 Me8-f3 4.HAf7-f4 EAg2-g4 #
c) bHAf7-->a3
1...Kc3-c4 2.Ke3-e4 EAb3-f2 3.Rf3-f5 Me8-f3 4.HAa3-e3 Mf3-d2 #
d) bRf3-->d5
1...Me8-f2 2.HAf7-f3 Kc3-b4 3.Ke3-d4 EAb3-f4 4.HAf3-e4 Mf2-e5 #