Rat Defense: Fuller Gambit
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Statistics from Lichess
3,271 games: White 47.0% / Draw 4.6% / Black 48.5%
| Next move | Games | White / Draw / BlackW / D / B |
|---|---|---|
| 1,0691,069 | ||
| 990990 | ||
| 571571 | ||
| 325325 | ||
| 154154 | ||
| 128128 | ||
| 1818 | ||
| 88 |
Rated Lichess games between players rated 1600 to 2500, from the Lichess opening explorer, updated Oct 30, 2026
Engine evaluation
+0.47 White is slightly better
Best play: 4. Nf3 Nxd5 5. d4 e6 6. a3 g6 7. c4 Ne7 8. Nc3 Bg7
Stockfish 19, depth 30, after the line's last move. Scores are in pawns, from White's side.
Overview
Rat Defense: Fuller Gambit (ECO B00, Semi-Open Games) is a gambit in the Rat Defense: Harmonist, reached after 1. e4 d6 2. f4 d5 3. exd5 Nf6 (3 moves).
In 3,271 rated Lichess games between players rated 1600 to 2500, White won 47.0%, Black 48.5% and 4.6% were drawn. White's most played move here is 4. c4, in 33% of those games.
Written from the Lichess opening list and explorer. Know this line well? Write about it.
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How to play against the Rat Defense: Fuller Gambit
4. d4 scores best for White: 52.2%, with White winning 49.8% and Black 45.5% of 325 games. The most played answer, 4. c4, scores lowest: 46.7% in 1,069 games. Stockfish's first choice is 4. Nf3.
Main answers: those played in at least 5% of these games. Score: White's wins plus half the draws, in rated Lichess games between players rated 1600 to 2500. How to play against other popular openings
Cite this page
Caissa Codex. “Rat Defense: Fuller Gambit (B00)”. Lichess data as of 30 Oct 2026. https://chesscodex.org/openings/rat-defense-fuller-gambit