Black to play and win (hard)
 ← 
 → 
1...Na4! 2.Rxc7 ( 2.Nxe4 Rxc1 3.Rxd5 Nc3+ 4.Nxc3 R1xc3 ) 2...Nac3+ 3.Rxc3 Nxc3+ 4.Kf1 Nxd1 0-1
[Event "?"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "1-0"]
[FEN "2r5/2r2pkp/pp4p1/2np4/4n3/1P2P3/P2NKPPP/2RRN3 b - - 0 1"]
[SetUp "1"]

1...Na4 $1 2.Rxc7 ( 2.Nxe4 Rxc1 3.Rxd5 Nc3+ 4.Nxc3 R1xc3 ) 2...Nac3+ 3.Rxc3
Nxc3+ 4.Kf1 Nxd1 0-1