Guess my move

Just for fun, a game played 2008 in German Oberliga (3rd league). Not a tactics exercise though, just an intelligent guessing.

What did Sarg0n play with the white pieces?

lichess.org/analysis/standard/2rq1rk1/p4ppp/1p6/3pN3/Pb2n3/1P1Q4/1BP1RPPP/R5K1

I dont know what did Sargon play but my first idea was to sac the rook but then after Bc3 it doesnt look good. Then I came with c4 trying to undermine the knight and also the c3 square looks better now.

White has to be careful to hold the balance. I don't know how I had found the move but is was a pretty cool one though.

Nd7 attacking the rook on f8 and the idea of Rxe4 if Black captures on d7 looks interesting.It also opens the a1-h8 diagonal for the queen and the bishop.

Indeed! A smooth draw against FIDE-Elo 2300.

It is a pretty continuation, but is it the strongest? Is the simple 18 Nf3 not stronger, taking control of the blockade square d4? There must be some way to profit from the isolated queen's pawn. A draw with white is no great accomplishment. Kasparov did not get anything substantial from the position either