ECO B06 · Pterodactyl Defense

Pterodactyl Defense: Eastern, Anhanguera

1. e4 g6 2. d4 Bg7 3. Nc3 c5 4. Be3

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Black to move. The arrow shows Stockfish’s best move.
Best move

4… cxd4+0.61

White is slightly better. Stockfish 18, depth 18.

Analyze this position

In the Pterodactyl Defense: Eastern, Anhanguera (B06), reached after 1. e4 g6 2. d4 Bg7 3. Nc3 c5 4. Be3, Stockfish 18 recommends 4… cxd4 for Black. White is slightly better (+0.61).

Top engine moves

  1. +0.614… cxd4 5. Bxd4 Nf6 6. e5 Ng8 7. e6 f6 8. exd7+ Bxd7 9. Qd3
  2. +0.614… Bxd4 5. Bxd4 cxd4 6. Qxd4 Nf6 7. O-O-O Nc6 8. Qe3 d6 9. a3
  3. +0.714… Qa5 5. Nf3 d6 6. Qd2 cxd4 7. Nxd4 Nc6 8. O-O-O Bd7 9. f4

Frequently asked questions

What is the best move in the Pterodactyl Defense: Eastern, Anhanguera?
After 1. e4 g6 2. d4 Bg7 3. Nc3 c5 4. Be3, Stockfish 18 at depth 18 recommends 4… cxd4 for Black, continuing 5. Bxd4 Nf6 6. e5 Ng8 7. e6 f6 8. exd7+ Bxd7 9. Qd3. White is slightly better (+0.61). The next best moves are 4… Bxd4 (+0.61) and 4… Qa5 (+0.71).
Is the Pterodactyl Defense: Eastern, Anhanguera a good opening?
Stockfish rates the position at +0.61: white is slightly better. Evaluations this early in the game are small, so practical results depend far more on knowing the plans and typical structures than on the engine's number.
What is the ECO code of the Pterodactyl Defense: Eastern, Anhanguera?
B06. ECO codes classify chess openings from A00 to E99; B is the volume for semi-open games (other than the French).

Opening names from the Lichess opening book (CC0). Pieces by Colin M.L. Burnett (GPLv2+).