Renju Openings Guide: Swap2, Standard Positions & First Move Principles

📋 Table of Contents

Why Openings Matter More in Renju
The First Move: Center Start
The Swap2 Opening Protocol
The Soosyrv-8 System
Other Opening Protocols
Common Opening Position Families
Opening Principles for Black
Opening Principles for White
How to Study Renju Openings

1. Why Openings Matter More in Renju

In standard Gomoku, openings matter — but either player can play almost anywhere on the early moves without critical consequence. In Renju, the opening carries significantly more weight for several reasons:

Forbidden move landscape is established early. The first few stones determine which intersections Black can and cannot safely play later. A poorly structured opening can close off key attacking squares for Black from the very beginning.
Color assignment is determined by the opening offer. Unlike in Gomoku, players do not simply choose their color beforehand. The swap2 protocol ties color selection to the specific opening position offered — which means the opening is simultaneously a negotiation about who plays which side.
Early patterns define the mid-game. Because Renju games are won through precise pattern development, the opening architecture — where the first 5–7 stones are placed — determines which attacking and defensive formations are viable for the next 20 moves.

🔑 Opening Insight: In Renju, the opening is not just about the first few moves — it is a fairness mechanism (swap2), a strategic framework (which patterns become viable), and a forbidden-move risk landscape (which squares are safe) all at once.

2. The First Move: Center Start

In tournament Renju, Black's first stone is always placed at the center intersection of the 15×15 board. In standard Renju notation (using letters a–o for columns and numbers 1–15 for rows), this is position h8.

a b c d e f g h i j k l m n o ↑ 1 · · · · · · · · · · · · · · · (rows 2-7 empty) 8 · · · · · · · ● · · · · · · · ← Black's first stone at h8 (center) (rows 9-15 empty) 15 · · · · · · · · · · · · · · · Black always starts at the center in tournament play. White's second stone can be placed anywhere.

This forced center start prevents Black from opening in strategically dominant off-center positions and ensures both sides begin from a symmetrical starting point before the game diverges.

In casual and online play, the center-start rule is often not enforced — Black can play anywhere. However, playing to the center voluntarily is almost always the strongest first move regardless of rules, because the center provides influence in all eight directions.

3. The Swap2 Opening Protocol

Swap2 is the opening protocol used in most international Renju tournaments, including World Championship events. It was developed to eliminate the unfairness of a fixed color assignment — since Black holds a first-move advantage under Renju's rules, neither player should be forced into a color against their preference for the specific opening offered.

How Swap2 Works

Step 1 — The offer: One player (usually determined by lot or by tournament bracket) proposes an opening position by placing three stones on the board: two black and one white. The proposer can choose any three-stone arrangement they wish, including ones they have prepared in advance.

Example — A proposer offers this 3-stone position: a b c d e f g h i j k l m n o 8 · · · · · · · ● · · · · · · · (Black stone 1 at h8 — center, always) 9 · · · · · · · · · · · · · · · 9 · · · · · · · · ● · · · · · · (White stone at i9 — diagonal from center) 10 · · · · · · · · · ● · · · · · (Black stone 2 at j10 — further diagonal) A near-center three-stone position like this is common in casual Renju. Tournament openings use more precisely defined positions.

Step 2 — The response: The other player (the "responder") sees the three-stone position and chooses one of three options:

Play as Black — accept the position and take the Black side (two black stones already on the board). The proposer becomes White.
Play as White — accept the position and take the White side (one white stone already on the board). The proposer becomes Black.
Extend to five stones — add one more black stone and one more white stone to the board, then let the proposer choose which color to take. The responder takes the remaining color.

📜 Swap2 Logic: The proposer is incentivized to offer a balanced position. If it favors Black too much, the responder takes Black. If it favors White too much, the responder takes White. The only position where the proposer retains some control is a truly neutral one — where the responder might extend to five stones, restoring the proposer's color choice.

Why Swap2 Is Superior to Simple Swap

An earlier protocol called swap (or "simple swap") allowed the second player to either accept the first player's color choice or swap sides. Swap2 improves on this by giving the responder the option to add more stones before choosing, making it much harder for a proposer to offer a position that is secretly favorable to one side through deep preparation.

4. The Soosyrv-8 System

The Soosyrv-8 opening system (named after Estonian Renju master Andres Soosyrv) is used in many European championships as a way to further reduce preparation advantages. Instead of allowing any three-stone offer, Soosyrv-8 uses a fixed set of eight official three-stone opening positions.

At the start of each game, one of the eight positions is randomly selected (by draw or tournament software). Both players then apply swap2-style color selection from the chosen position. This means:

Neither player can pre-prepare a specifically skewed three-stone offer.
Both players must be familiar with all eight standard positions.
The game still involves color negotiation, but from a pre-defined neutral starting point.

The eight Soosyrv-8 positions include near-center configurations with different geometric relationships between the three stones — direct diagonal, one-step offset, symmetric placements, and so on. Competitive players study each of the eight positions extensively as both Black and White.

✓ For Beginners: You do not need to memorize the Soosyrv-8 positions to enjoy Renju. Swap2 with any reasonable three-stone offer is the normal starting point for casual and online play. Soosyrv-8 is a tournament-level refinement.

5. Other Opening Protocols

Protocol	Description	Used In
Swap2	3-stone offer; responder plays as Black, White, or adds 2 more stones and proposer picks color	Current RIF international standard
Soosyrv-8	Random selection from 8 fixed 3-stone positions; color selection via swap2 logic	European championships, some WRF events
Yamaguchi	First 3 moves fixed (d11 pattern); White offers N candidate fifth-stone positions; Black chooses one and picks color	Japan National Championships historically
Taraguchi-10	3-stone offer with swap; if responder declines swap, proposer places 5th stone from 10 offered options and responder picks color	Some Asian regional events
Ning	Black places 2 stones; White places 1 stone; Black places another stone; then swap option for Black	Chinese regional events
Simple Swap	Black places 3 stones; White can swap colors or continue as White	Older tournaments; now largely replaced by Swap2

6. Common Opening Position Families

Regardless of which opening protocol is used, Renju openings can be grouped into families based on the geometric relationship between the first three stones. Understanding these families helps you recognize similar positions and transfer strategic knowledge across games.

Direct Diagonal (d11 family)

Most Common

Black's first stone is at center (h8). Black's second stone is at j10 — two steps diagonally. White's stone is at i9 — the diagonal step between them. This creates a tight cluster of three stones near the center. Games from this family tend to be tactically dense from the very start, with both sides needing to navigate the forbidden move landscape carefully from move 4 onward.

Offset Diagonal

Balanced

The two black stones are separated by two or more empty intersections with White's stone placed asymmetrically. These openings tend to create more space between the early threats, giving both sides more freedom in the mid-game. They are often preferred by players who favor slower, positional play.

Symmetric / Mirror Positions

Theoretical

Some opening proposals place the three stones in a rotationally symmetric pattern. These positions are theoretically interesting because either player's response looks similar in most directions. In practice, even subtle asymmetries in how Black and White respond create very different mid-game positions.

Long-Distance Opening

Positional

Black's second stone is placed far from the center (five or more intersections away). These positions divide the board into more clearly separated zones and usually lead to longer, more strategic games where both sides develop independent formations before they collide in the mid-board.

7. Opening Principles for Black

Whether Black's opening position was chosen by Black or inherited through swap2, these principles guide good early play:

Assess the forbidden move risk immediately. As soon as your three opening stones are on the board, identify which key intersections near your stones would be forbidden for Black if played. Mark these mentally and ensure your opening development plan avoids them.
Develop toward the board's open spaces. Early Black stones should point toward empty regions with expansion room, not toward the edges or toward White's stones. Flexibility early creates attacking options later.
Do not rush to create open threes. In the first 5–8 moves, Black's priority is structure, not immediate threats. Premature open three creation invites White to block while simultaneously narrowing Black's future options by closing potential forbidden-move-safe paths.
Control the tempo through positioning. Place stones that create multiple future threat directions — even if none are immediate. A stone that influences three potential lines is more valuable than one that builds a single urgent threat that White can easily block.

8. Opening Principles for White

Respond to real threats, not imaginary ones. In the opening, White should not panic-block Black's early formations if they are not yet threatening. Premature defensive moves waste White's turns and concede the initiative.
Create your own threats while defending. The best White moves do double duty — they block a Black threat while simultaneously creating a White formation. Look for stones that serve both purposes.
Watch the forbidden move landscape. As Black develops opening formations, watch for intersections where Black's natural attacking continuations would be forbidden. White can sometimes steer toward positions that channel Black's future moves toward those forbidden squares.
Build broad rather than narrow. White benefits from a wide spread of influence across the board. A White formation that threatens in multiple zones is harder for Black to neutralize than a concentrated single-line White attack.

9. How to Study Renju Openings

Opening study in Renju is different from, say, chess — there is no single authoritative "book" of opening theory with forcing lines. Instead, opening knowledge comes from understanding principles and positions:

Study the eight Soosyrv-8 positions from both sides. Even if you never play Soosyrv-8 tournaments, these eight positions represent the most-analyzed opening configurations and expose you to the widest range of early-game structures.
Review published master games from the RIF World Championships. Pay attention to moves 4–12, where the opening transitions into the mid-game. How do strong players develop their stones while managing forbidden move risks?
Experiment in practice games. Use our Renju vs Computer page to try out different opening ideas in a low-stakes environment. Play the same opening 5–10 times to understand its recurring patterns and problems.
Study your own games. After each loss, look specifically at whether your opening setup constrained your mid-game options. Did you create a forbidden move risk zone early that your opponent later exploited?

✓ Best First Step: Before memorizing specific opening lines, learn to identify — from any three-stone position — which key intersections near those stones are immediately forbidden for Black. This situational awareness is more transferable than memorized sequences.

Practice Your Opening Theory

The best way to internalize opening principles is to play. Challenge real opponents online or experiment with positions against the computer.

▶ Play Renju Online ▶ Practice vs Computer