Full Report for Sygo by Christian Freeling

Full Report for Sygo by Christian Freeling

Have the highest score at the end of the game.

Generated at 22/04/2020, 18:20 from 1000 logged games.


Start Position


Each turn, either:


If a group loses its last liberty, it is captured. Unlike Go, captured stones are flipped to the opposite color.


Territorial, as per go. There is no komi.


General comments:

Play: Combinatorial

Family: Go

Mechanism(s): Connection,Pattern

Components: Board

BGG Stats

BGG EntrySygo
BGG Rating7.5
BGG Weight0

BGG Ratings and Comments

mrraow8An extremely interesting riff on Go. The flip-captures mean there's no need for a ko rule, and the growth rules lead to a shorter game than go on a similar sized board. Interesting trade-offs between growing and seeding; as you'd expect from the Symple mechanism. I think I prefer this to Symple; Sygo feels sharper, in the sense that each stone placement is more critical. In Symple, where you grow seems much less important than the simple fact that you are growing; but that may just be my flawed understanding of the game.
milomilo122N/AWhen I first learned about the concept behind this game, I was dubious - it seemed like a recipe for chaos, what with the possibility for placing a large number of stones on a single turn. I've since learned that many people react similarly to the idea. However, when I played the game my doubts dissolved. It works waaaaaaay better than the rules suggest it would. In fact it's a very good game, maybe even a great one. Update: after a few further attempts to play this game, having to place all those stones on a single turn has gotten a little frustrating for me. Analysis overload.
orangeblood7Another fun design from Christian, and another one that he calls among his most important… among his six core games (the others being Grand Chess, Dameo, Emergo, Symple, and Storisende). Of course it will inevitably be compared to Symple (because it uses the same move protocol). However, once you get into your first game, you’ll see it’s not really like Symple at all. Once the game is finished, the scoring is pretty much like Go. But to get there… really wild. When you capture stones they’re flipped, Othello-like, to your own color. This can present problems as you of course are trying to form two eyes in each of your groups. It’s also really fun to think about things like what would be a normal joseki in Go. Should I try a 3-3 invasion? Maybe not, given that you don’t always connect to the whole group, and thus would lose a turn adding to each of your other groups. Anyway, I can’t really say if I prefer Symple or Sygo at this point, but I do like them both very much!

Kolomogorov Complexity Estimate

Size (bytes)37802
Reference Size10293

Ai Ai calculates the size of the implementation, and compares it to the Ai Ai implementation of the simplest possible game (which just fills the board). Note that this estimate may include some graphics and heuristics code as well as the game logic. See the wikipedia entry for more details.

Playout Complexity Estimate

Playouts per second822.04 (1216.49µs/playout)
Reference Size1438641.92 (0.70µs/playout)
Ratio (low is good)1750.09

Tavener complexity: the heat generated by playing every possible instance of a game with a perfectly efficient programme. Since this is not possible to calculate, Ai Ai calculates the number of random playouts per second and compares it to the fastest non-trivial Ai Ai game (Connect 4). This ratio gives a practical indication of how complex the game is. Combine this with the computational state space, and you can get an idea of how strong the default (MCTS-based) AI will be.

Playout/Search Speed

LabelIts/sSDNodes/sSDGame lengthSD
Random playout8336318,4182,07138212

Random: 10 second warmup for the hotspot compiler. 100 trials of 1000ms each.

Other: 100 playouts, means calculated over the first 5 moves only to avoid distortion due to speedup at end of game.

Mirroring Strategies

Rotation (Half turn) lost each game as expected.
Reflection (X axis) lost each game as expected.
Reflection (Y axis) lost each game as expected.
Copy last move lost each game as expected.

Mirroring strategies attempt to copy the previous move. On first move, they will attempt to play in the centre. If neither of these are possible, they will pick a random move. Each entry represents a different form of copying; direct copy, reflection in either the X or Y axis, half-turn rotation.

Win % By Player (Bias)

1: White win %52.80±3.10Includes draws = 50%
2: Black win %47.20±3.08Includes draws = 50%
Draw %1.00Percentage of games where all players draw.
Decisive %99.00Percentage of games with a single winner.
Samples1000Quantity of logged games played

Note: that win/loss statistics may vary depending on thinking time (horizon effect, etc.), bad heuristics, bugs, and other factors, so should be taken with a pinch of salt. (Given perfect play, any game of pure skill will always end in the same result.)

Note: Ai Ai differentiates between states where all players draw or win or lose; this is mostly to support cooperative games.

Levels of Play

AIStrong WinsDrawsStrong Losses#GamesStrong Win%p1 Win%Game Length
Grand Unified UCT(U1-T,rSel=s, secs=0.01)36023894.7455.26371.03
Grand Unified UCT(U1-T,rSel=s, secs=0.03)361124974.4947.96299.63
Grand Unified UCT(U1-T,rSel=s, secs=0.07)361114876.0444.79305.19
Grand Unified UCT(U1-T,rSel=s, secs=0.20)36044090.0067.50336.20

Level of Play: Strong beats Weak 60% of the time (lower bound with 90% confidence).

Draw%, p1 win% and game length may give some indication of trends as AI strength increases; but be aware that the AI can introduce bias due to horizon effects, poor heuristics, etc.


Game length352.70 
Branching factor86.09 
Complexity10^540.45Based on game length and branching factor
Samples1000Quantity of logged games played

Computational complexity (where present) is an estimate of the game tree reachable through actual play. For each game in turn, Ai Ai marks the positions reached in a hashtable, then counts the number of new moves added to the table. Once all moves are applied, it treats this sequence as a geometric progression and calculates the sum as n-> infinity.

Move Classification

Distinct actions363Number of distinct moves (e.g. "e4") regardless of position in game tree
Good moves359A good move is selected by the AI more than the average
Bad moves4A bad move is selected by the AI less than the average
Samples1000Quantity of logged games played

Change in Material Per Turn

This chart is based on a single playout, and gives a feel for the change in material over the course of a game.


Table: branching factor per turn.

Action Types per Turn

This chart is based on a single playout, and gives a feel for the types of moves available over the course of a game.

Red: removal, Black: move, Blue: Add, Grey: pass, Purple: swap sides, Brown: other.


This chart shows the best move value with respect to the active player; the orange line represents the value of doing nothing (null move).

The lead changed on 30% of the game turns. Ai Ai found 15 critical turns (turns with only one good option).

Overall, this playout was 62.40% hot.

Position Heatmap

This chart shows the relative temperature of all moves each turn. Colour range: black (worst), red, orange(even), yellow, white(best).

Good/Effective moves

MeasureAll playersPlayer 1Player 2
Mean % of effective moves51.2648.4254.19
Mean no. of effective moves13.3513.5713.12
Effective game space10^321.8310^163.6110^158.21
Mean % of good moves17.167.7326.84
Mean no. of good moves11.3513.678.96
Good move game space10^198.7510^97.9210^100.83

These figures were calculated over a single game.

An effective move is one with score 0.1 of the best move (including the best move). -1 (loss) <= score <= 1 (win)

A good move has a score > 0. Note that when there are no good moves, an multiplier of 1 is used for the game spce calculation.

Opening Heatmap

Colour shows the success ratio of this play over the first 10moves; black < red < yellow < white.

Size shows the frequency this move is played.

Unique Positions Reachable at Depth


Note: most games do not take board rotation and reflection into consideration.
Multi-part turns could be treated as the same or different depth depending on the implementation.
Counts to depth N include all moves reachable at lower depths.
Inaccuracies may also exist due to hash collisions, but Ai Ai uses 64-bit hashes so these will be a very small fraction of a percentage point.

Shortest Game(s)

No solutions found to depth 2.



Black to win in 14 moves

Selection criteria: first move must be unique, and not forced to avoid losing. Beyond that, Puzzles will be rated by the product of [total move]/[best moves] at each step, and the best puzzles selected.