1.Ba5+!

Try : 1.Bb4+? Kc2 2.Ra8 Kd3! (no 2...c6+? 3.Kc4 b5+ 4.Kc5 Kb3 5.Rh3+ Bd3 6.Rxd3+ Kc2 7.Rc3+ Kd1 8.Rd8+ Ke1 9.Rc2+ Kf1 10.Ng3+ Kg1 11.Rdd2 b1Q 12.Rg2#) 3.Rd8+ Ke2]

 

1...Rc2 2.Tc6+! …..

 

With two lines :

 

A) 2...bxc6+ 3.Kc4 c5 4.Ng3! (4.Nf4? c6 5.Be1 Kd1 6.Bb4+ Kc2 7.Bxc5 Kd2 8.Rh2 with

 

a.1.) 8.. Ke1 9.Bb4+ Kd1 10.Rh1+ Kc2 11.Nf5 c5 12.Ne3#

 

a.2.) 8...Kd1 9.Kc3 Be4 10.Rd2+ Kc1 11.Ne2+ Kb1 12.Rd1#

 

a.3.) 8...Kc1 9.Be3+ Kd1 10.Rd2+ Ke1 11.Kc3 Be4 12.Bf2#´

 

 

B) 2...Kd3 3.Re1 bxc6+ 4.Kc5 Kc2 5.Kc4 c5 6.Ng3 c6 7.Re2+ Kd1 8.Rd2+ Ke1 9.Rg2+ Kd1 10.Kc3 with

 

b.1.) 10.. Ke1 11.Kb3+ Kd1 12.Rg1#

 

b.2.) 10...Bd3 11.Rg1+ Bf1 12.Rxf1#

 

Culmination  in matte from 5 different boxes univocally