Chess Openings Lab
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Caro-Kann Defense: Martian Gambit

The Martian Gambit is 5.Ng5 Bg6 6.N1f3 h6 7.Ne6, a knight thrown onto e6 in the Classical Variation. The knight forks the queen on d8 and bishop on f8, so Black should take it with ...fxe6 and accept the piece, while White hopes for light-square pressure against e6 and the king.

Moves
1.e4 c6 2.d4 d5 3.Nd2 dxe4 4.Nxe4 Bf5 5.Ng5 Bg6 6.N1f3 h6 7.Ne6
ECO
B18
Engine
−1.40 · a clear edge for Black (Stockfish 17.1, depth 20)
Played
29 games in our lichess sample
White scores
65.5%

Key ideas for both sides

White

  • After ...fxe6, trade bishops with Bd3 to open the h5-e8 diagonal and the light squares near Black's king.
  • Look for queen checks such as Qg6+ once the g6 bishop is gone and the f7 square is empty.
  • Castle quickly and bring a rook to e1 to target the weak pawn on e6.

Black

  • Take with 7...fxe6. A queen move lets White trade the knight for the f8 bishop and the extra piece is gone.
  • After Bd3 Bxd3 Qxd3, check with ...Qa5+ and then bring the queen to f5 to cover the light squares.
  • Develop the knights to f6 and d7, and keep the king safe before trying to use the extra piece.
  • Trade queens when possible. Without queens, White has no attack and the extra piece wins.

Plans and pawn structure

After ...fxe6 Black is a full piece up but has a weak pawn on e6 and an exposed light-square diagonal toward e8. White's plan is Bd3 to trade bishops, then Qd3 and Qg6+ ideas, short castling and a rook to e1 against e6. Black defends with ...Qa5+ and ...Qf5, offering a queen trade, then ...Nf6, ...Nd7 and king safety. Once Black consolidates, the extra piece decides, so White must keep the initiative going.

Where the engine's main line heads: White pawn d4, no e-pawns for White, no d-pawn for Black. White has a pawn on d4 and no e-pawn; Black has no d-pawn. White has more central space; Black's pieces are free and the d4 pawn is a target.

What the engine plays from here

Stockfish 17.1 at depth 20 rates the position −1.40: a clear edge for Black. Its three top choices for Black:

  1. −1.40 7...fxe6 8.Bd3 Bxd3 9.Qxd3 Qa5+ 10.Bd2
  2. +1.34 7...Qd6 8.Nxf8 Kxf8 9.Be2 e6 10.O-O
  3. +1.59 7...Qc8 8.Nxf8 Kxf8 9.Bd3 Bxd3 10.Qxd3

Pawns, from White's side.

How to play against it

As Black, take on e6 with the f-pawn. Any queen move allows Nxf8 and gives White an easy game. Then meet Bd3 with ...Bxd3 and check on a5 to bring the queen to f5. Do not grab more pawns: develop and trade pieces.

Questions

What are the moves of the Caro-Kann Defense: Martian Gambit?

The Caro-Kann Defense: Martian Gambit starts 1.e4 c6 2.d4 d5 3.Nd2 dxe4 4.Nxe4 Bf5 5.Ng5 Bg6 6.N1f3 h6 7.Ne6. Its ECO code is B18.

Is the Caro-Kann Defense: Martian Gambit good for White?

Stockfish 17.1 rates the position −1.40 at depth 20, which is a clear edge for Black. A dubious gambit that only works against unprepared opponents; Black should win with accurate defense.

What is the main idea of the Caro-Kann Defense: Martian Gambit?

White sacrifices a knight on e6 to open lines toward Black's king. Black should take with the f-pawn, defend the light squares with ...Qa5+ and ...Qf5, and keep the extra piece.

What should Black play next?

The engine's first choice is fxe6, with Qd6 and Qc8 close behind. 7...fxe6 takes the piece, and Black then trades bishops and brings the queen to f5.

Updated October 2026. Sources and method.