Sicilian Defense: Four Knights Variation

-14%
B561.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 Nc6
Feb 20, 2026
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TL;DR

Black's move 5...d6 protects the recently developed knight from being attacked. A pawn move is thus in order, since both knights are developed to good squares, and the Bishop on c8 now has the option, but not the obligation, to develop to a good square once white makes their intentions known.

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Sicilian Defense: Four Knights Variation: A Complete Guide
Sicilian Defense: Four Knights Variation - Opening Moves
Summary

The Sicilian Defense: Four Knights Variation arises after 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 Nc6 and falls under ECO code B56. With both knights already on good squares, the earlier ...d6 serves the useful purpose of shielding the f6 knight from being chased, while the c8 bishop retains the flexibility to develop in different directions depending on how White proceeds. Among White's options, Bg5 stands out as arguably the strongest and is the move to expect from well-prepared opponents. It pins the king's knight, sets the stage for queenside castling, and serves as the gateway to the Richter-Rauzer Attack, named after Vsevolod Alfredovich Rauser. With 5.6 million Lichess games across all rating levels, it is one of the most popular openings.

History and Notable Players

It arises from the Sicilian Defense: Open Variation. Among the most prolific practitioners on the White side are Viswanathan Anand (242 games), Vlastimil Jansa (238 games), Oleg Korneev (231 games). On the Black side, notable exponents include Lubomir Ftacnik (297 games), Loek Van Wely (271 games), Boris Gelfand (260 games).

Statistics

Based on 5.6 million Lichess games across all rating levels:

  • White wins: 47.7%
  • Black wins: 47.3%
  • Draws: 5%

The statistics show a roughly balanced opening where both sides have equal chances.

Main Lines and Variations

After 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 Nc6, the main continuations include:

Each of these lines leads to distinct types of positions and requires its own understanding of the resulting pawn structures and piece placements.

Common Mistakes to Avoid

  • Ignoring the opponent's kingside attack: In many Sicilian lines, White will castle queenside and push pawns toward your king. If you don't create counterplay on the queenside or in the center, White's attack will arrive first.

Practice on Chessiverse

The best way to learn the Sicilian Defense: Four Knights Variation is through practice. On Chessiverse, you can play chess against computer opponents that specialize in this opening. Our AI bots range from beginner to grandmaster level, each with unique playing styles — from aggressive attackers to solid defenders. Choose a bot that matches your rating and work your way up as you master the opening's key ideas.

Quick Facts

Main Line1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 Nc6
FENr1bqkb1r/pp2pppp/2np1n2/8/3NP3/2N5/PPP2PPP/R1BQKB1R w KQkq - 3 6
DifficultyExpert
Style

Theoretician openings have deep, well-studied lines where knowledge of specific variations gives a significant advantage. Preparation and memorization of key lines are essential.

5,583,902games on Lichess
47.7%
5%
47.3%
White wins Draws Black wins

Top Players

As White
As Black

Data from Lichess opening explorer (blitz & rapid)

Most Popular At2500
SharpnessSharp

Popularity by Rating

Percentage of all games at each rating bracket that feature this opening.

Data from Lichess opening explorer (blitz & rapid games)

Theory Adherence by Rating

How often players choose the single most popular move at this position. Higher = more predictable play.

White to move after the opening line

Popularity Over Time

Share of all Lichess blitz + rapid games featuring this opening, by year.

Top Moves by Rating

White to move after the opening line

RatingMost Popular2nd3rd
400Nxc639.6%Bb524.5%Be39.7%
1000Nxc634.6%Bb527.7%Be311%
1200Bb528%Nxc624.9%Be314.8%
1400Bb523.6%Be319.8%Nxc617.5%
1600Be325.4%Bb517.3%Bg514%
1800Be328.4%Bg514.3%Bc412.5%
2000Be325.8%Bg519.1%Bc414.6%
2200Bg535.1%Bc417.9%Be314.1%
2500Bg553%Bc417%Be28.1%

Popularity by Time Control

Bullet
0.10%2.6M
Blitz
0.13%4.7M
Rapid
0.08%888K
2% more decisive in bullet
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Training Recommendations

Targeted drills using our bots' unique playstyles to sharpen your skills in this opening.

First Steps in the Sicilian Defense

beginner

Carla Tempo is an aggressive Savage who thrives in complex positions. A good opponent to learn the opening basics in this opening.

♟️

Sharpening Your Play in the Sicilian Defense

intermediate

Qhawe Pawn is a balanced Mediator with a well-rounded approach. A good opponent to practice your skills in this opening.

Proving Your Preparation in the Sicilian Defense

skilled

Sue Chef is a defensive Guardian who prefers to simplify, while Paolo Pawnte is an aggressive Savage who thrives in complex positions. Practice at the skilled level to test your preparation.

♟️

Master-Level Challenge in the Sicilian Defense

advanced

Gretchen Whisker is a balanced Mediator with a well-rounded approach. A good opponent to practice your skills in this opening.

Frequently Asked Questions

What is the Sicilian Defense: Four Knights Variation?

The Sicilian Defense: Four Knights Variation begins with 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 Nc6 and is classified under ECO code B56. Black's move 5...d6 protects the recently developed knight from being attacked.

Is the Sicilian Defense: Four Knights Variation good for beginners?

The Sicilian Defense: Four Knights Variation can be played at any level. Beginners should focus on understanding the key strategic ideas rather than memorizing long theoretical lines. Our AI bots at various rating levels provide a great way to practice the opening concepts.

What are the win rates for the Sicilian Defense: Four Knights Variation?

Across 5.6 million Lichess games, White wins 47.7% of the time, Black wins 47.3%, and 5% are drawn. Notable master practitioners on the White side include Viswanathan Anand and Vlastimil Jansa. On the Black side, Lubomir Ftacnik and Loek Van Wely are among the most frequent practitioners.

How can I practice the Sicilian Defense: Four Knights Variation?

On Chessiverse, you can practice the Sicilian Defense: Four Knights Variation against AI bots specifically designed to play this opening. Our bots range from beginner (around 878 rating) to advanced (2338+ rating), so you can find the right challenge for your level.

Written by

Chessiverse
Chessiverse TeamOpening Guides

Expert chess content backed by opening theory and our database of 600+ AI bots with unique playing styles and opening repertoires.

Practice This Opening on Chessiverse

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