White is a Rook down, and plays...1.c4...The practical best move!The objective best is1.Nd7+Kc82.Nxf8Rxf8White's only a piece down, which on paper, is better than being down a Rook down. But anyway, Black has a material advantage, and it's much harder to crack open their Queenside, making their King feel safe.1....bxc41...dxc42.Nxb7Kxb73.Qxc6+2.b5...Remember strategy 5: to sacrifice fearlessly.2....axb52...cxb53.Nxb7Kxb74.Qxd5+gives White good counterplay.3.a6Bc8is a mistake.3...Ba8is accurate.4.a7+Kc8And Black still has an advantage.4.a7+Ka85.Qxd5cxd55...Rf66.Qxc6+Rxc67.Bxc6+Bb78.Bxb7#6.Bxd5+Bb77.Bxb7#