Chess Openings Lab
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King's Pawn Game: Tortoise Opening

The Tortoise Opening is 1.e4 e5 2.Bd3, putting the bishop in front of White's own d-pawn. Black can develop freely with ...Nf6, ...Bc5 and quick castling, while White plans to reroute the bishop later, often to c4, and catch up in development.

Moves
1.e4 e5 2.Bd3
ECO
C20
Engine
−0.25 · level (Stockfish 17.1, depth 20)
Played
981 games in our lichess sample
White scores
43.3%

Key ideas for both sides

White

  • Follow with Nf3, Nc3 and O-O; the bishop can later go to c4 as in the engine lines.
  • Use c3 and a later bishop retreat to c2 if you want to free the d-pawn for d4.
  • Accept that the d2 pawn and c1 bishop are blocked for now; do not rush d3 too early.
  • Watch the f2 square once Black's bishop reaches c5.

Black

  • 2...Nf6 develops and attacks e4, which the bishop on d3 only defends once.
  • Put the bishop on c5, aiming at f2, and castle quickly.
  • Use ...Re8 and ...d5 to hit the center while White's bishop blocks the d-pawn.
  • Develop ...Nc6 before ...d6 so the pawn does not block the queen's lines.

Plans and pawn structure

White's bishop on d3 blocks the d-pawn and the c1 bishop, so Black gets a lead in development. Black should play ...Nf6, ...Bc5, ...O-O and ...Re8, then break with ...d5 to open the center. White tries to fix the setup with Bc4 and d3, or c3 and a bishop retreat to c2. In the sample, White scored only 43.3%, a sign that the extra time spent hurts.

Where the engine's main line heads: Open game: e4 against e5. An open game: e4 against e5. Development, the f7 and f2 squares, and the d4 or d5 break are what count.

What the engine plays from here

Stockfish 17.1 at depth 20 rates the position −0.25: level. Its three top choices for Black:

  1. −0.25 2...Nf6 3.Nc3 Bc5 4.Nf3 O-O 5.O-O
  2. −0.19 2...Nc6 3.Nf3 Nf6 4.Nc3 Bc5 5.Bc4
  3. −0.11 2...Bc5 3.Nf3 Nc6 4.Bc4 Nf6 5.d3

Pawns, from White's side.

How it scores on lichess

981 rated lichess games reached this position; White scored 43.3%.

under 120042.7%
1200–159943.4%
1600–199944.7%

Light: White wins. Grey: draws. Dark: Black wins. About the sample.

How to play against it

As Black, develop fast with ...Nf6, ...Bc5 and ...O-O. Do not attack the bishop on d3 with pawns; it is misplaced and you want it to stay there. Aim for ...d5 to open lines while White is still untangling.

Questions

What are the moves of the King's Pawn Game: Tortoise Opening?

The King's Pawn Game: Tortoise Opening starts 1.e4 e5 2.Bd3. Its ECO code is C20.

Is the King's Pawn Game: Tortoise Opening good for White?

Stockfish 17.1 rates the position −0.25 at depth 20, which is level. In 981 lichess games from our sample, White scored 43.3%. A slow surprise for White that gives Black an easy and pleasant game with simple development.

What is the main idea of the King's Pawn Game: Tortoise Opening?

White develops the bishop to d3, where it blocks the d-pawn. Black gains time with ...Nf6, ...Bc5 and ...O-O, then opens the center with ...d5.

What should Black play next?

The engine's first choice is Nf6, with Nc6 and Bc5 close behind. 2...Nf6 hits e4 and develops, using the time White lost with the awkward bishop.

Updated October 2026. Sources and method.