The Eastern, Pteranodon is a variation of the Pterodactyl Defense, catalogued as ECO B06. The line runs 1. e4 g6 2. d4 Bg7 3. Nc3 c5 4. dxc5 Bxc3+ 5. bxc3 Qa5, reaching the position shown below after 10 half-moves.
White holds the centre with pawns on e4. Development is level at one minor pieces each, and White is up a pawn of material. It is White to move after five moves. White has doubled pawns on the c-file; White’s c- and a-files pawns are isolated; White has the bishop pair.
On the Pterodactyl Defense generally: ECO A40. A chess opening with 34 known variations.
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See all 17 Pterodactyl Defense variations →
The Eastern, Pteranodon goes 1. e4 g6 2. d4 Bg7 3. Nc3 c5 4. dxc5 Bxc3+ 5. bxc3 Qa5. It is a variation of the Pterodactyl Defense and is catalogued as ECO B06.
The Eastern, Pteranodon is ECO B06. ECO codes group openings by their move order, so nearby codes cover closely related lines of the Pterodactyl Defense.
Stockfish evaluates the position after 1. e4 g6 2. d4 Bg7 3. Nc3 c5 4. dxc5 Bxc3+ 5. bxc3 Qa5 at +0.80 at depth 18, which is a small but real edge for White. Engine evaluation is only a starting point — at club level the practical value of a line is mostly about whether you know its plans better than your opponent does.
White holds the centre with pawns on e4. Development is level at one minor pieces each, and White is up a pawn of material. It is White to move. White has doubled pawns on the c-file; White’s c- and a-files pawns are isolated; White has the bishop pair.