Key ideas
- With Nc3, g3 and Bg2 against the same set-up from Black (...Nc6, ...g6 and ...Bg7), the positions are slow and manoeuvring. The first side to break the symmetry with a well-timed b4, d4 or e4 (or ...b5, ...d5 or ...e5) usually takes the initiative.
- In the Four Knights Variation (2.Nf3 Nf6 3.Nc3 Nc6), White often plays d4, and after ...cxd4 and Nxd4 the game resembles an Open Sicilian with White's pawn already on c4. With e4 to follow, a Maroczy-type bind is possible.
- When White opens the centre with d4, Black has two characteristic answers: the Hedgehog, with pawns on a6, b6, d6 and e6 waiting for ...b5 or ...d5, and the Rubinstein line, in which ...d5, ...Nxd5 and ...Nc7 challenge the centre with pieces.
- The Botvinnik System (pawns on c4 and e4 with Nc3, g3 and Bg2) grips d5 at the cost of a hole on d4. Black can play the same idea in reverse with ...e5, which is the Botvinnik System Reversed.
Plans for White
Use the extra tempo. Develop with Nc3, g3, Bg2, Nf3 and short castling, then choose a break: d4 to open the position, or a3, Rb1 and b4 for queenside space. In the open lines, d4, Nxd4 and e4 can give a lasting grip on d5.
Plans for Black
Pick a structure you understand: copy White and wait for ...d5 or ...b5 at the right moment, set up the Hedgehog after an exchange on d4, or play ...e5 with a firm hold on d4. Do not prolong the symmetry once White's extra move starts to tell.
For the wider picture, see the English Opening guide.