Mastering Mini Go

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A Complete Guide to the 9×9 Go Board

by Mark Tomlinson

Buy the full book at gobooks.com

The 9×9 board distills Go to its essence—a knife fight in a phone booth where every move counts and games finish in minutes, not hours. Mastering Mini Go is your complete guide to this compact battlefield, transforming it from a beginner’s training ground into a sophisticated tactical arena. Drawing on cutting-edge AI analysis and his years of experience at the top of the OGS 9×9 ladder, attorney and amateur dan Mark Tomlinson reveals why the center dominates, how Black must pressure relentlessly, and why White’s patient style can exploit the tiniest mistakes.

Packed with over 400 diagrams, professional game commentaries, and dozens of named openings, Mastering Mini Go delivers actionable knowledge for players of all levels. Whether you’re relatively new to Go or a dan player seeking a fresh challenge, Mastering Mini Go provides the tactical principles you need to win on the small board, where reading depth trumps opening memorization and games are often decided by half a point.

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Copyright Page

Copyright © 2025 by Mark Tomlinson

All rights reserved.

About the Author

Mark Tomlinson was born in 1989 in Portland, Oregon. Growing up, there was always a chess board on the coffee table, but Go captured his attention much later, in 2008. He graduated from Biola University in 2011, having attended and later served as vice president of the university Go club. In 2014, he graduated from Pepperdine (Caruso) School of Law, where he also participated in the Woodland Hills Go Club. He is now a senior attorney in Bakersfield, California, where he relaunched the Bakersfield Go Club and continued playing online, eventually advancing to amateur 5 dan and claiming the #1 spot on the online-go.com (OGS) 9×9 ladder many times, including while writing this book. He co-hosted the “Crazy Nines” YouTube series with Stephen Hu, provided input to 81 Little Lions: An Introduction to the 9×9 Board for Advanced Beginners by Immanuel deVillers and the KataGo 9×9 opening books by David Wu, and created his own 9×9 opening book based on roughly 400 professional games.

Contents

Introduction

Chapter 1: Basic Principles

Counting the Score

The First Move

The chapters in gray are included only in the full book.

Black’s Basic Strategy

White’s Basic Strategy

Finding Territorial Balance

The Group Number Limitation

Chapter 2: 9×9 Tactics

Attachment

Belly Attachment

Nose Tesuji

Cut Across

Clamp

Shortage of Liberties

Wedge

Two-Step Hane

Footsweep

Squeeze

Eye-Making Tesuji

Exercises

Introduction to 9×9 Openings

Chapter 3: Tengen Openings

Sword

Orthodox

Windmill

Hand Fan

Curveball

Soccer Juggling

Jump Attack

Cross Line

Almost Equilateral 1

Headbutt

Almost Equilateral 2

Pendulum

Almost Equilateral 3

Side Attachment

Other Tengen Openings

Chapter 4: Hoshi Openings

Black Boomerang

Bean Throwing

Big Flower

Flower

Lunar Eclipse

Blackjack

Swing

Horse Head

Airship

Submarine

Other Hoshi Openings

Chapter 5: Takamoku Openings

New Orthodox

Andromeda

Slider

Secret Agent 033

White Slice

Kodachi

Jump Attachment!

Zazen

Boots

Other Takamoku Openings

Chapter 6: Territorial Openings

Mokuhazushi Main Line

Sea Fairy

Avoiding Transpositions

Other Mokuhazushi Openings

Komoku

Sansan

Chapter 7: Midgame

Reading

Attacking

Cutting

Invading

Handling Invasions

Trading Spaces

Chapter 8: Endgame

Life and Death

Common Corner Shapes

Prioritizing Endgame Threats

Calculating Move Values

Endgame Flexibility and Reading

Chapter 9: Game Commentaries

Murakawa Daisuke v. Iyama Yuta (2013)

Yamada Kimio v. Cho Chikun (1994)

Appendix A: Glossary

Appendix B: Resources and Further Study

Acknowledgements

Buy This Book

Introduction

The game of 9×9 Go, also called Mini Go, contrasts sharply with its larger counterpart. If the standard 19×19 board is a sprawling battlefield, then 9×9 is a knife fight in a phone booth. Its brevity and intense tactical focus make it an ideal starting point for new players, as I discovered firsthand in my second year of college after stumbling upon a game in the Student Union Building. As I sat for my first game, the players swapped their large board for a smaller one. That first game marked the beginning of a beautiful, slightly obsessive relationship with Go, one that would follow a kind of U-shaped trajectory: starting small, progressing to 19×19, and ultimately leading me back to the unique joy of Mini Go.

Depth of 9×9

Despite its small size, 9×9 offers surprising depth. Even Cho Chikun, one of the greatest players of all time, remarked while observing a 9×9 game, “It’s surprising how difficult it is.” He’s hardly alone in this feeling. Other professional players have echoed this sentiment, noting that even late-game situations can become violent, hard to read, and subject to human error.

Mathematically, 9×9 is about as complex as chess, boasting significantly more possible game positions than atoms in the observable universe. 9×9 is also about as long as chess, lasting about 50 moves on average compared to over 200 for 19×19. While 19×19 can sometimes feel as baffling and time-consuming as assembling IKEA furniture, 9×9 is more like downing a quick cup of coffee. The brisk pace makes it ideal for a quick mental workout or for those with limited time.

This quality is worth appreciating. 9×9 is neither trivial nor overwhelming. It sits comfortably in the Goldilocks zone of board sizes. The dimensions may seem arbitrary, but there’s a logic to its design. The square grid gives the board a harmonious bias-free geometry. The odd number of gridlines gives the board a true center point, providing ammunition against mirroring tactics. Within these limits, 5×5 and 7×7 may make for fun party games, much like tic-tac-toe or Connect Four, but are just a bit too simple for serious study. 5×5 is solved, and 7×7 very nearly so.

Mini Go is where the magic happens. It’s the smallest size that expresses the full essence of Go—invasions, reductions, sacrifices, ko fights, everything. Its accessibility also makes it the perfect dojo for beginners. You learn faster on 9×9 because you can play more games in the same time, and your missteps are punished more quickly and are more apparent, which means more immediate feedback on why you lost (or why you won!).

History of 9×9

Does 9×9 have a history? Indeed it does, though it’s a tale told in whispers rather than records. While specific references are elusive before the mid-20th century, archaeology confirms that the now-standard 19×19 grid wasn’t always the rule. 17×17 boards were common in China and Tibet, and a roof tile from a guard house of the tomb of Emperor Han Jing Di (188–141 B.C.) suggests a 13×13 grid. This tradition of playing on smaller boards makes it plausible, though not provable, that 9×9 was also explored. Even so, the evidence is likely lost for a reason embedded in the nature of the game itself. A quick, informal match wouldn’t require a wooden or stone set but would more likely have been drawn on materials long since turned to dust or even scratched into the dirt, leaving no artifact behind.

The historical trail, cold for centuries, picks up again with a legend from Japan’s Edo period (1603–1868). The legend speaks of a specific tactical sequence—a probing move known today as the Sword—that was allegedly discovered during this period. It’s the kind of inventive play that feels both ancient and modern, but unfortunately, no game records from the period survive to confirm the tale.

The earliest specific references to 9×9 Go date to 1968, when Go Seigen and Miyamoto Naoki played two games to try to decide the proper komi for this board size. There’s no mention in these records that 9×9 was novel or invented at this time, so it’s reasonable to assume that 9×9 preexisted these games but was neglected, perhaps misjudged as too simple. That they played only two games before concluding, incorrectly, that the proper komi was 4.0 suggests that 9×9 was dismissed as a curiosity rather than studied in depth.

By 1978, Winfried Dörholt’s book Das japanische Brettspiel Go presented 9×9 naturally as a method for introducing the rules to beginners. Much like the Japanese records before it, the book presents 9×9 not as a novelty but as something already familiar, suggesting the board’s quiet, parallel life in Europe.

In 1987, Yomiuri TV brought 9×9 into living rooms across Japan with a delightful Sunday morning program called Mini Go One-Game Match (ミニ碁一番勝負). What began as a 15-minute amateur showcase soon grew into a 30-minute professional featurette, blending education with competition. Hundreds of games from the series survive, archived on GoBase.org and elsewhere.

When AI researchers entered the scene, 9×9 became their testbed. Early programs like Fuego and Igowin opened 9×9 to new audiences. And in 2010, Fuego even beat a professional player, though at a humble 2-kyu level, which probably says more about the thin state of 9×9 theory than about the program’s prowess.

The launch of the GoQuest server in 2013 was another turning point. Suddenly, players around the world had a dedicated arena for competitive 9×9. Opening theory deepened, rivalries flourished, and a lively community formed that continues to thrive there and beyond.

All of these things come together to make 9×9 a cherished niche within the Go community. The format condenses all the drama of Go into quick matches that still carry the weight of centuries, and yes, still leaves time for dinner.

Purpose of This Book

This book is the result of years of research and practice. My heart went into it. Along with my guts, intestines, and diaphragm. I pulled a few muscles. I had a few breakdowns. If you saw what I did to make this book, you’d have called 9–1–1. But if, by the time you finish the first few chapters, you’ll feel better equipped to face opponents on the 9×9 board, then I’ll consider this book a success. As Herbert Spencer once said, “The great aim of education is not knowledge but action.” And this is an action book, your path to understanding and appreciating Mini Go.

Whether you’re a 19×19 veteran looking for a new challenge, a casual player curious about 9×9, or a relative newbie to Go, this book will give you the tools you need to understand 9×9 and deepen your appreciation for this board size. We’ll cover dozens of openings, dissect the tactics and techniques that define success in the midgame, and tie it up with a nice little bow at the endgame. But don’t worry; it’s not all didactic ranting. We’ll have some laughs along the way, marvel at the brilliance (and sometimes absurdity) of the game, and hopefully, you’ll come to love this tiny board’s vast universe of possibilities as much as I do.

Rules Used in 9×9

Rules on 9×9 are nearly identical to 19×19. Advanced analysis of the 9×9 board has revealed that Black wins by 6 points under Japanese rules and by 7 points under Chinese rules, so komi (White’s compensation for playing second) is usually set to reflect this, plus or minus a fractional amount if draws are to be avoided. For newer players, komi this high on a board one quarter the size of 19×19 can feel unfair. But the small size also increases the value of playing first, so a solid understanding of opening theory (a major focus of this book) will help you overcome this feeling. If you read this book, digest it, sleep with it under your pillow, and practice diligently, you’ll overcome that feeling faster than you think.

For now, don’t worry too much about the differences between rule sets. This book uses Chinese rules with 7.0 komi—the settings for GoQuest—but the strategies apply equally well under either system. And when they don’t, this book will say so.

Notation in This Book

This book uses diagrams from both constructed situations and real games. For clarity, previously shown move numbers are omitted. Only new moves are numbered.

Beneath many diagrams, you’ll find some handy situation judgment marks. These quick guides reveal who’s ahead, behind, or evenly matched:

“B+” means favorable for Black.

“W+” means favorable for White.

“=” means an equal position.

With all that out of the way, grab your stones (or your phone, or your tablet, etc.), find a comfortable spot (chair, sofa, bed, traditional Japanese zabuton, whatever floats your boat; just try to be yourself), and let’s dive into the miniature mayhem of Mini Go!

How to Use This Book

This book contains over 400 diagrams and hundreds of variations. If that sounds intimidating, it shouldn’t be. You needn’t memorize everything, and you certainly don’t need to study it linearly like a textbook.

Here’s how I recommend approaching it based on your experience level:

For Complete Beginners:

1. Read Chapter 1 thoroughly
2. Study Chapter 2 and complete all exercises
3. Choose ONE opening from Chapters 3–5 to learn deeply
4. Skip to Chapter 8 for essential life-and-death patterns
5. Return to more openings as you gain experience

For Intermediate Players (approaching single-digit kyu level):

1. Skim Chapter 1, focusing on sections you find challenging
2. Review Chapter 2, testing yourself on exercises
3. Study 2–3 openings from your preferred first move
4. Read Chapters 7–8 carefully for midgame and endgame principles
5. Use the book as a reference during game review

For Advanced Players (approaching dan level):

1. Focus on opening chapters (3–6) for theoretical depth
2. Study the advanced (★★★) openings
3. Use Chapter 7 for strategic refinement
4. Study Chapter 9’s professional games

Study Tips:

Don’t try to memorize everything
Focus on understanding why moves work
Play games between study sessions
Review your losses using relevant book sections
Revisit chapters as your understanding deepens

Chapter 1
Basic Principles

Counting the Score

“Wait. Counting? I was promised opening theory!” Ok, fair enough. But if you can’t tell who’s ahead, how are you going to know if your moves are any good? Charging into the opening without knowing how to measure your progress is like hiking up a mountain blindfolded and then complaining when you inevitably stumble or get cut on something. In 9×9, the real danger isn’t just losing points; it’s the cascade of unintended consequences that follow from not thinking things all the way through. This matters as much in Go as it does in life, as Stephen Covey explores in “The 7 Habits of Highly Effective People,” where one of the habits is “Begin with the end in mind.” So the first thing we’re going to do is take the blindfold off and learn to tell a winning position from a losing one. We start here, at the end.

Counting diagram 1

Consider Diagram 1. How quickly can you say who won? If you need more than a few seconds, then I have a tip for you. In Chinese rules and 7.0 komi, a draw occurs when White controls 37 points. These 37-points can be visualized as four rows plus one stone. Fewer than 37 points means that Black wins, while more than 37 means that White wins. Counting Black is unnecessary in this system because, unless the position includes a seki, Black necessarily controls the remaining 44 points. White is counted because counting 37 is faster than counting 44, but you could count Black’s score if you prefer (visualizing five rows minus one stone).

Visualizing the points like this makes scoring Diagram 1 easy. White has four rows of nine stones, plus two stones, or 38 stones. White wins by two points, as each stone in Chinese rules shifts the score by two points: one gained for White; one missed by Black.

Counting diagram 2

Diagram 2 is counted in much the same way. White has four rows (separated into 5×4 and 4×4 boxes) plus one stone. That’s 37 points—a draw. Simple, right? Once you know this trick, you can score most positions in seconds, regardless of your skill level. Seki changes the math, but don’t worry too much about that. Focus on the general rule for now.

Let’s solidify your understanding with three exercises.

Counting exercise 1

Who won this game and by how much? Start by visualizing four rows for White, then adjust for any black stones inside or white stones outside your visualization.

Counting exercise 2

Do the same for Exercise 2. Who is leading and by how much?

Counting exercise 3

Are you getting it? Now try a harder one. Using what you’ve learned, think about how you might go about counting this position quickly, then determine the victor and margin of victory.

Counting exercise 1: Solution

Let’s review each exercise in turn. First, visualize four rows for White (marked with a box). Three black stones within this area must be swapped with living white stones outside the area (marked X). White doesn’t have enough stones to make this swap, so White has clearly lost. Being one stone short of four rows, White has 35 stones—two stones shy of the 37-point benchmark—and loses by four points.

Counting exercise 2: Solution

For Exercise 2, we must again visualize four rows for White and mentally swap four black stones within this area with living white stones outside it (marked X). This swap leaves White with four surplus stones, or 40 stones in total, three more than the 37 required for parity. White wins by six points.

Counting exercise 3: solution

Many games don’t end as neatly and need a different approach. Exercise 3, for example, has five rows of four in the lower left, but rows six through nine aren’t easily visualized. In positions like these, it’s often helpful to remember that four rows of nine is equivalent to nine rows of four, which means counting by fours can be efficient. Here, you might visualize the lower five rows of four and manually count the remaining four—A, B, C, D. Of course, no one will scold you for counting by twos or even ones. The important thing is that you count, which automatically places you ahead of many other players you’re likely to encounter. No matter how you count, you should find that White has 37 stones in Exercise 3 (displayed as five rows of four, four others labeled A to D, and an extra stone at X), indicating a draw.

The First Move

The first lesson of 9×9 Go, after counting and scoring, is to unlearn the principles of the 19×19 board. The familiar opening hierarchy of corners, then sides, then center inverts. On the 9×9 board, the center is the most efficient because territorial value no longer scales with proximity to the edges. More fundamentally, the compressed space collapses the distinction between influence and territory, as there’s no space for influence to develop separately from territory. And because the typical corner zones from the 19×19 board overlap on a board as small as 9×9, a stone near the center influences all four corners at once, making it more efficient than locking down any single corner.

This compression fundamentally transforms the opening. While 19×19 openings feature josekis and other sequences of moves to establish territorial frameworks that gradually convert influence into territory, a 9×9 game reaches direct fighting within the first few moves. Games are decided by tactical precision in close combat rather than through large-scale framework battles.

On larger boards, strong players use stones on one side of the board to influence battles on the other side. On a 9×9 board, the center is the other side of the board from every edge. Therefore, the opening moves should be a fight for central control. This control makes subsequent fighting easier, which in turn makes taking territory easier. Even so, this strategy is a means to an end. You must still secure points, and a player who falls too far behind in solid territory will find their central position to be a hollow crown.

Using Tromp-Taylor like rules, komi 7, Black to play

The image above shows an analysis of the opening position by the Go engine KataGo, based on tens of trillions of simulated games under Tromp-Taylor rules (similar to Chinese rules). This analysis reveals four distinct first moves for Black that lead to a draw with perfect play, labeled 1 to 4. Of these, the “big three”—hoshi (1), tengen (2), and takamoku (3)—are the most popular and favored among strong players because of their central position and tactical flexibility. While hoshi and takamoku also appear in 19×19 opening theory, they serve a different purpose here. They’re not moves to secure a corner but to launch a battle, aiming outward toward the center rather than inward toward the edge. Mokuhazushi (4), the only optimal move with a clear territorial aim, can also achieve a draw but is less popular, being further from the center and offering comparatively fewer tactical options.

Other first moves don’t hold up as well. Komoku (5) aims for a corner enclosure, but enclosures lose much of their power when the small board size encourages players to divide its territory down the middle. Komoku was once thought to achieve draw if Black continued precisely enough, but deep analysis now shows that komoku is a losing move if White plays the unique best reply (the opposite hoshi) and continues optimally. Sansan (6) is weaker still, sitting too deep in one corner, far from the center where the decisive action occurs. Don’t take my word for it. Just turn to almost any diagram in this book and notice how many 3–3 points remain empty even well into the middlegame. Sansan gives Black the fewest tactical options and is vulnerable to a well-prepared opponent, with ∆ and a handful of other moves effectively refuting it. Needless to say, lower moves (7 through 15) are even weaker and should be avoided altogether.

Chapter 2
9×9 Tactics

Imagine, if you will, a plumber who has never picked up a wrench, or an electrician who has never touched a multimeter. Imagine a golfer stepping onto the fairway without half the clubs in the bag, or a piano tuner showing up without a hammer or felt mutes. Each can still go through the motions of their profession, but without the proper tools, their work will be clumsy at best. So too in 9×9 Go: the “tools” of the trade are the tactics and clever plays (called “tesuji”) that let you develop your position and pry apart your opponent’s. This knowledge is essential for any serious player. You can certainly enjoy the game without it, but if you don’t know what tools are available, you’ll struggle to find real success. Reading is the muscle of Go, but tactics are its language. And in the knife-fight-in-a-phone-booth metaphor, those tactics mark the difference between emerging unscathed or staggering out battered and bruised. With this in mind, let’s review some of the tactics most relevant to 9×9.

Attachment

Attachment

＞＜ ▶︎

An attachment, also called a contact play, is a move played directly next to an opposing stone without touching any friendly stones. By removing a liberty from the opposing stone, it often prompts a local response from the opponent, keeping sente. When played from above, it presses the opponent low while maximizing territory behind the attachment. Conversely, when played from below or from the side, it serves as a useful launchpad for invasion, creating a fighting situation deep within the opponent’s area. An attachment can also function as a “leaning attack,” building strength in one area to enable a decisive move elsewhere. “Make a feint to the east while attacking in the west,” as the saying goes. This principle can apply even in 9×9. While an attachment generally reinforces the stone under attack, making it questionable when played out of the blue on a 19×19 board, it becomes an essential technique in 9×9. On such a small board, the trade-off is worthwhile.

Attachments can arise naturally in all sorts of positions. They also form useful combinations with other techniques worth knowing.

Attach-staircase

＞＜ ▶︎

White 1 and 3 form a staircase pattern simply called attach-staircase. This aggressive way of playing exposes a cutting point in the opponent’s shape and a cutting point in your own shape. But this shouldn’t discourage you from playing it, as the cutting point in your own shape is often manageable. In fact, players facing attach-staircase often atari from outside, inducing you to fix that weakness while their own weakness lingers.

Attach-extend

＞＜ ▶︎

A more secure way of playing compared with attach-staircase is to extend after the attachment, as with White 3 above. This operation generally occurs when the staircase doesn’t work well or when the position requires a more stable shape. Note that attach-extend (tsuke-nobi, in Japanese) is contrasted with attach-and-pull-back (tsuke-hiki) in which White 3 is at A.

Attach-block

＞＜ ▶︎

Attach-block describes this pattern. You can think of it as a variation of the attach-staircase, supported by a tiger’s mouth. Attach-block offers the same benefit as its cousin pattern: it generates cutting points that weaken the opponent’s shape.

Attach-crosscut

＞＜ ▶︎

Attach-crosscut is a more complex way of playing than attach-extend. It shines brightest when you judge an opponent’s hane as an overplay, but it sets up many tactical options even when the position is even. The crosscut stone can lead to immediate fighting or be sacrificed, as when making sabaki in the opponent’s area of influence.

From this point on, variations will include brief continuations showing how each tactic works in practice.

Belly Attachment

Belly attachment

＞＜ ▶︎

Black 1 above is a belly attachment—a contact play made on the side of two opposing stones. White A is the “belly” being attached to, while B represents White’s “head.” Here, this attachment lets Black take move 3 in sente, when playing 2 or 3 alone would be gote, allowing White to play around 5.

Exercise 1

Exercise 1
White to play

＞＜ ▶︎

Solution 1

Correct answer

＞＜ ▶︎

This capturing race is solved with a belly attachment. This attachment forces Black into an unwinnable miai. Any attempt to gain liberties through one gap lets White occupy the other.

Introduction to 9×9 Openings

This book is like a quadruple cheeseburger on mini buns—the two ends too small to realistically hold the feast in the middle. The first bun covered the basic fundamentals and tactics, while the end bun addresses the midgame and endgame phases. Everything between? Well, you can guess from the heading. It’s the opening, and we’re going to feast on it for four chapters: one for each “big three” opening move and another for territorial openings.

Now, some players claim that 9×9 has almost no opening, that within a few moves you either plunge into a full-board fight or enter the early endgame. This is partially true, but the implication that you can go it alone and just read your way to victory through sheer force of will is dubious. Because it’s impossible to read out all variations from move 1, 9×9 benefits tremendously from even a little opening study. And these chapters will explore a great many openings, though there are too many variations to cover in their entirety. Knowing the theory of each opening will elevate your play and increase your success.

9×9 is closer to chess than to 19×19 in terms of opening theory, with labyrinthian opening variations, some with many variations to deal with and some with fewer. Think of these chapters as your guide through this 9×9 jungle. 9×9 openings are categorized by name, mostly from the GoQuest server, which alerts you during play when a named opening is played. You’ll want to know these openings, along with certain popular but unnamed openings.

These aren’t just memorization drills. The goal is to understand the principles and ideas behind the openings. We’ll explore the reasoning behind each move so you can understand the themes and problems that these openings present. This will give you the confidence to handle any deviation that your opponent throws your way.

Each chapter covers the main openings for each opening point, loosely organized with the most common responses first. Each opening also includes a (subjective) difficulty assessment to help you prioritize your study: beginner-friendly (☆☆★), intermediate (☆★★), or advanced (★★★). If you’re new to an opening point, start with the simpler openings to understand the strategic themes, then gradually work toward the more complex openings. More advanced openings, while useful to know, require strong reading and can be postponed until you’re comfortable with the basic patterns. Some opening positions also have informal English names that aren’t officially recognized, shown in quotation marks. Some openings aren’t recommended because it advantages one player, but the variations are still worth learning, both because you may need to face them and because the ideas underlying the refutations can carry over to other positions.

Here’s a quick note on the symbols we’ll use in the diagrams themselves:

Letters (A, B, etc.) mark the main lines—solid moves that tend to give the best results regardless of rule set.

Triangles (∆) mark alternatives that draw under Chinese rules but may not under Japanese rules with perfect play. This typically occurs because a one-point loss matters under Japanese rules but has minimal effect under Chinese rules, as the score changes in increments of two.

Squares (□) mark the opposite: moves that draw under Japanese rules but may not under Chinese rules. This occurs due to subtle rule differences, such as whether surrounded empty points in seki count. Squares therefore reflect more complex variations where these differences may come into play.

Lettered moves are the standard choices, but don’t overlook the others. Even unmarked moves can be useful for surprising an opponent, playing around a disadvantageous komi, or steering the game into sharper, less predictable territory. These symbols aren’t commandments. They’re simply signposts to help you understand the possibilities in each position. The same is true of the variations themselves, which are just a fraction of the possibilities available. And although these markings have been checked with AI, there’s also the possibility that some symbols are incorrect, as 9×9 Go is unsolved and no solution is expected in the near future.

With that out of the way, let’s dive into the openings!