Philidor Defense

1. e4White plays e4, claiming the centre.
2. e5Black replies e5, the classical open game.
3. Nf3Nf3 develops and attacks e5.
4. d6d6 — the Philidor. Black defends the pawn with a pawn. It is completely solid, but it blocks the f8 bishop's diagonal, which is the opening's lasting drawback.
5. d4d4! White challenges the centre immediately and gains space.
6. Nf6Black develops Nf6, attacking e4 and refusing to release the central tension yet.
7. Nc3Nc3 defends e4 and completes the natural development.
8. Nbd7Nbd7! The Hanham setup. The knight supports e5 and f6 without blocking anything — this is the modern, respectable way to play the Philidor.
9. Bc4Bc4 develops the bishop to its most active square, eyeing f7.
10. Be7Black plays Be7, a modest but necessary developing move that prepares castling.
11. O-OWhite castles, connecting the rooks and completing the opening.
12. O-OBlack castles too. The position is solid but cramped — Stockfish reads about +0.5 for White, a bit more than a normal opening edge, which is the price of the passive setup.

The trap that catches beginners over and over. 3...Bg4 looks like a healthy pin, but the bishop is not actually pinning anything important. 4.dxe5! exploits it: after the forced sequence White ends up with the queen on f3 hitting f7 and b7, plus the bishop coming to c4. Stockfish reads about +2.3 for White — close to winning.

1. e4White plays e4.
2. e5Black plays e5.
3. Nf3Nf3 attacks e5.
4. d6d6 — the Philidor.
5. d4d4 challenges the centre.
6. Bg4Bg4?! The natural-looking pin, and the mistake. The bishop looks active, but it is not pinning the knight to anything that matters.
7. dxe5dxe5! The refutation. White captures and the bishop on g4 is suddenly loose — Black cannot simply recapture on e5 because of the pressure that follows.
8. Bxf3Black takes on f3, which is forced — otherwise the piece is lost outright.
9. Qxf3White recaptures with the queen, which now stares at f7 and b7 from a dominant square.
10. dxe5Black regains the pawn on e5, but the damage is structural: the bishop pair is gone and f7 is chronically weak.
11. Bc4Bc4! The second piece joins the attack on f7. Black cannot defend everything comfortably.
12. Nf6Nf6 develops and blocks the worst of it, but White is close to winning — Stockfish reads about +2.3.

The Antoshin Variation, where Black releases the central tension immediately with 3...exd4. The upside is freedom — the pieces get out easily. The downside is that White keeps a permanent space advantage in the centre. Sound and much less passive than the main line; the engine reads about +0.4 for White.

1. e4White plays e4.
2. e5Black plays e5.
3. Nf3Nf3 attacks the pawn.
4. d6d6 defends it.
5. d4d4 challenges the centre.
6. exd4exd4! Black trades immediately rather than maintaining the tension. This frees the position at the cost of the centre.
7. Nxd4White recaptures with the knight, which sits centralised on d4.
8. Nf6Black develops Nf6, hitting e4.
9. Nc3Nc3 defends e4 and develops.
10. Be7Be7 prepares castling — and note the bishop is no longer blocked by a pawn on e5.
11. Be2Be2 is modest and safe, keeping the bishop out of the way of ...Nc6 ideas.
12. O-OBlack castles. Comfortable and playable, though White has more space: about +0.4.

White develops the bishop before committing the d-pawn, keeping the option of transposing back into the main lines. Often used to avoid the Antoshin structures. Play usually transposes into standard Philidor positions anyway, and Stockfish reads about +0.5 for White.

1. e4White plays e4.
2. e5Black plays e5.
3. Nf3Nf3 attacks e5.
4. d6d6 — the Philidor.
5. Bc4Bc4!? White develops the bishop first, aiming at f7 before deciding what to do with the d-pawn.
6. Be7Black plays Be7, calmly developing and preparing to castle.
7. d4Now d4 comes with the bishop already on its best square.
8. exd4Black trades on d4.
9. Nxd4White recaptures with the knight.
10. Nf6Nf6 develops and attacks e4.
11. Nc3Nc3 defends the pawn.
12. O-OBlack castles. A normal Philidor position with a small, comfortable pull for White — around +0.5.