Chess Opening Theory/1. e4/1...c5/2. Nf3/2...d6/3. d4/3...cxd4/4. Nxd4/4...Nf6/5. Nc3/5...a6/6. Be3/6...e5/7. Nb3/7...Be6

= Najdorf Sicilian, English Attack = '''Moves: 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6.Be3 e5 7.Nb3 Be6'''

This is the best move. The Black bishop covers d5 from e6 and also points at the queenside when White castles there. Black also contemplates using c4 as a piece outpost. Black's position retains maximum flexibility, as in almost all variations Black plays ...Be7, ...Nbd7, ...O-O, ...Rc8, and ...Nb6 in some order.

Theory table
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1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5. Nc3 a6 6.Be3 e5 7.Nb3 Be6