About brainGO: A Companion-Style 4×4 Go Puzzle Game
⏱ Read ~6 min · Updated July 2026 · Part of: Learn Go
brainGO is a companion-style 4×4 Go puzzle game. It distills the ancient game of Go into sixteen points, turning it into a calm daily brain exercise anyone can play — no manual, no scoring, no numbers.
What brainGO is
- Pure 4×4 capture puzzles. You learn Go by capturing, not by reading rules. Every puzzle is solved by the brainGO algorithmic engine — the "correct answer" is provably correct.
- A companion, not a critic. A character that remembers your name, encourages without shaming, and celebrates with you. The point isn't the puzzle — it's the daily ritual.
- All ages. Designed for kids (no number anxiety, instant feedback), seniors (large fonts, high contrast, short loops), and adults (a two-minute shareable break, like Wordle).
brainGO's original: one-stone variations
brainGO has a feature no one else can do — one-stone variations: same board, add or remove one stone, the outcome flips. We compute every ±1-stone variation for each position, letting you see which stone actually decides the game. This is impossible on boards above 4×4 (too many combinations) — only 4×4 can be fully solved.
Where the puzzles come from
Every puzzle is generated by our own solving algorithm — exhaustive search, difficulty-graded, provably correct. We use no one else's copyrighted puzzle sets. We're inspired by the teaching philosophy of small-board capture go (the "capture go / Atari Go" tradition used worldwide for beginners), not by copying any specific puzzle collection.
Our technical moat
| Aspect | What brainGO does | Why others can't |
|---|---|---|
| Engine precision | 4×4 exhaustive, every answer unique and provable | Large boards can't be exhausted |
| One-stone variations | ±1-stone comparison, showing each stone's weight | Needs a fully solved state space |
| Copyright-free | Generated by our own algorithm | Doesn't depend on published puzzle sets |
| Companion sprite | Instant feedback + voice + personality | Most apps only have scores/percentiles |
What brainGO is not
- Not a 19×19 AI match.
- Not a gambling or betting tool.
- Not a medical device, not dementia treatment. We say "gets your brain moving," not "prevents dementia" — the science is inconclusive.
Our honest stance
A lot of "brain training" marketing is louder than the science behind it. We shrink the claims to what's real: a daily puzzle is a good habit, is satisfying, and beats scrolling your phone. That's the guarantee we make.
Start playing
Pick a puzzle, place a stone. The companion sprite will guide you from there.
👉 Play brainGO — your first puzzle
FAQ
What is brainGO? What does it do?
4×4 Go capture puzzles — Go distilled to 16 points, learning Go's core (calculation) through captures, one daily puzzle, with a companion sprite, for all ages. Not a 19×19 match, not medical, not gambling.
Where do the puzzles come from?
Generated by our own brainGO algorithmic engine — exhaustive 4×4 search, precise, difficulty-graded, copyright-free. No puzzle sets copied.
What are one-stone variations?
brainGO's original feature: same board ±1 stone, the outcome can flip. The engine computes every variation, showing you "which stone is the key stone." Only 4×4 can be fully solved (larger boards can't).
Can brainGO prevent dementia?
No. Scientific evidence is inconclusive. brainGO gets your brain moving, is fun, and is worth two minutes daily — but it's not medicine. For memory concerns, see a clinician.
Is brainGO free?
The core daily puzzle is always free. A family plan may come later (player plays, family pays to see activity). The core experience won't be paywalled.
Why 4×4, not 9×9 or 19×19?
4×4 = 16 points, roughly 43 million reachable states — one of the few board sizes an engine can fully solve, meaning every puzzle's answer is mathematically provable, not an AI guess. 9×9 (~10^38 states) and 19×19 (far more) can only be approximated with Monte Carlo tree search or neural networks, which can never offer a single provably-best move. The 16-point board also lets kids and seniors see the whole position at once, never feel overwhelmed, and finish a puzzle in two minutes — exactly the scale a daily ritual needs. If you want full games, play on OGS or GoKifu; brainGO goes the other direction, distilling Go into calculation puzzles.
Can I play if I've never played Go?
Yes — brainGO is built for people who have never touched Go. You don't need to read any rules first. Open the first puzzle, place a stone by intuition, and the companion sprite instantly tells you whether it captured. Capturing is the most primal move in Go, predating any formal rule in human intuition (even toddlers grasp "surround it, take it"). brainGO flips the usual learning path: build hand-feel for captures first, and after dozens of puzzles the rules (liberty, eye, atari) surface in your mind on their own. Most players understand what "liberty" means within their first 10 puzzles — faster than any beginner book.