Sicilian Defense: Four Knights Variation, Cobra Variation
1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3 Nf6 6. Ndb5 Bc5
The Sicilian Defense: Four Knights Variation, Cobra Variation is a chess opening classified as ECO B45, reached after 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3 Nf6 6. Ndb5 Bc5. It is a line of the Sicilian Defense. White is to move.
In 12.6 million rated Lichess games (blitz and slower), this position was reached 13 times by this move order. White won 31%, 7% were drawn and Black won 62%. The most popular continuation is 7. Nd6+ (54% of games).
Engine evaluation: +0.57 (Stockfish, depth 55; best line 7. Bf4 O-O 8. Bc7 Qe7 9. Bd6 Bxd6)
- ECO
- B45
- Moves
- 12 plies
- FEN
r1bqk2r/pp1p1ppp/2n1pn2/1Nb5/4P3/2N5/PPP2PPP/R1BQKB1R w KQkq - 5 7- PGN
1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3 Nf6 6. Ndb5 Bc5
Analyse with Stockfish · Board image (SVG) · Open on Lichess
Results by rating
| Average rating | Games | White / draw / Black |
|---|---|---|
| 1500-1999 | 1 | |
| 2000+ | 12 | |
| All | 13 |
Most played moves
| Move | Games | White / draw / Black |
|---|---|---|
| 7. Nd6+ | 7 (54%) | |
| 7. Bf4 | 4 (31%) | |
| 7. e5 | 2 (15%) |
Master games
179 over-the-board games are classified under this line (White 34%, draw 12%, Black 54%). The strongest:
- GM So, W. (2745) – GM Fabiano Caruana (2784) 1/2-1/2 · Saint Louis Rapid 2025 · 2025-08-12
- GM David Navara (2657) – GM Erigaisi Arjun (2782) 1-0 · FIDE World Bl Team Pool D · 2025-06-14
- GM Kacper Piorun (2611) – GM Nijat Abasov (2670) 0-1 · 2nd Prague Challengers · 2020-02-21
- GM Aleksandra Goryachkina (2553) – GM Alexey Sarana (2697) 0-1 · Titled Tue 27th Feb Early · 2024-02-27
- GM Yuniesky Quesada Perez (2591) – GM Shamsiddin Vokhidov (2644) 1-0 · Titled Tue 20th Jan 2026 · 2026-01-20
Highest-rated Lichess games
- IM beatles_21 (2767) – CM Romaa2011 (2790) 1/2-1/2 · 2026-09-03 · 180 + 0s
- FM Buyofl (2716) – CM Romaa2011 (2770) 0-1 · 2026-09-03 · 180 + 0s
- Yakamuzosan (2689) – CM Mikkel_Vinh (2680) 1-0 · 2026-09-04 · 180 + 0s
Comes from
Sicilian Defense: Four Knights Variation 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3 Nf6
More Sicilian Defense lines (all)
- Sicilian Defense (1. e4 c5) B20
- Sicilian Defense: Amazon Attack B20
- Sicilian Defense: Big Clamp Formation B20
- Sicilian Defense: Bowdler Attack B20
- Sicilian Defense: Brick Variation B20
- Sicilian Defense: Czerniak Attack B20
- Sicilian Defense: Czerniak Attack, Queen Fianchetto Variation B20
- Sicilian Defense: Euwe Attack, Prins Gambit B20
- Sicilian Defense: Gloria Variation B20
- Sicilian Defense: Grob Variation B20
- Sicilian Defense: Keres Variation B20
- Sicilian Defense: King David's Opening B20
Opening names and moves from the Lichess openings dataset; statistics from the Lichess open database, 2026-09 (CC0), sample of 12.6 million games, bots excluded; evaluations from Lichess cloud analysis (all CC0). Master games from The Week in Chess #920–#1664 by Mark Crowther, used with permission.