How to limit cheating in online go?

Published 21 May 2020 by antti (last edited 26 Jul 2020)
tags: tldr, cheating

The last 1–2 years have seen a sharp increase in cheating in online go, especially on higher dan levels. I, personally, have almost completely quit online go, as it not only takes a considerable amount time to find an opponent of similar level, but also the chances of the opponent’s consulting an ai are high. If I want to train with an ai, I’ll rather save my time and run KataGo directly on my computer. For some time, GoQuest seemed a safe haven for 13×13 go in this regard, but recently there is a pattern that if I get paired with a notably weaker player, ‘surprisingly’ the opponent makes no mistakes at all and almost directly follows the ai’s play.

While I (and probably many of you readers) prefer playing go on a real board, the reality right now is that there just are not enough go players around for that. For example chess has roughly ten times more players and chess playing sets are all around in cafés and bars – go is just simply not as widely spread. Therefore, at least for now, it seems to me that the spread of go is dependent on online playing servers.

Luckily, cheaters are more like the exception than the rule among lower and middle levels; there is nothing to ‘gain’ save for improvement and enjoyment, both of which the ai effectively removes – and if you keep on using the ai for winning games, eventually you will hit the upper end of the ranking spectrum. A part of me hopes that even in the higher rankings, cheating is a passing phenomenon and that people will soon realise that there is no purpose to it; but chess ai has been around for 20 years and the problem persists on chess servers, so probably this is wishful thinking.

The upper ranks’ ‘ai contamination’ is luckily a problem only for a small minority of players, and so the real challenge, I think, comes with online tournaments.

We saw with the Corona Cup that there is considerable demand for online go tournaments, at least now in the era of social distancing. When there are prizes and prestige at stake, and the risk of getting caught is slim at best, the number of cheaters sees a sharp increase. How should we try to battle this?

  • Remove the prizes or do not hold online tournaments at all. This is a bad solution, as online tournaments are a great opportunity for popularising and getting visibility for the game – and tournaments without prizes just don’t feel the same.
  • Have an arbitration board check games and results for possible cheaters. This is what we did at the Corona Cup, with Lukáš and me ending up researching several players’ tournament and non-tournament games. This solution is far from optimal, as it caused us a huge amount of work – and although we thought there were several highly suspicious cases, we were unable to gather enough evidence to convict any of them. The damage of wrongly convicting is far bigger than that of letting a cheater go loose, and so we figured we have to be extremely sure of a case – even a 99% subjective probability might not be good enough.
  • Develop an algorithm to catch cheaters. This is actually something that I am looking into right now. Having a reliable algorithm to catch cheaters would of course be an optimal solution, but the problem is that we have to create the algorithm first – and that is starting to look like an increasingly difficult project. I will elaborate on this more in a future post.
  • Set up proctored tournament settings. This is what professional go associations, for example the Japan Go Association, sometimes do. The players go to a common playing area where there is a proctor watching them play on a computer. As long as the proctor is reliable, this setting is virtually identical to a regular tournament setting. The downside is that this solution is not very cheap to set up, requiring a physical place where players gather, and so a lot of the benefits of playing online are lost.
  • Wild idea: set up a tournament go server that is accessed by vr headsets, for example the Oculus Quest. The Oculus Quest recognises when the user takes the headset off, and also when the user’s hands are not touching the controllers, making it infeasible for a player to consult an ai at the same time. This is not a foolproof solution – I will also elaborate on this in a later post – but I think it could solve cheating in low-stakes games. This solution would also make online go feel a bit more like playing on a real board, which should be a welcome feature to many. The problem in this solution is of course obvious: most people cannot afford a €479 headset just for playing go, and vr headsets may also cause nausea among some people.

Comments (7)

sig wrote 4 years ago:

Ha! VR is actually a very neat idea. The only thing you really need (in casual games) is making sure the person's full attention is on the game. It might not be enough when stakes are high enough for cheater to do minimal setup (asking another person to read out the moves, to act as an oracle of Sai :).

I guess if you play super fast blitz, you can similarly eliminate "trivial AI cheats" if you only have a couple seconds per move?

Obvious downside of the VR is, you want to implement it on a platform that isn't just a window with a go board (because then it wouldn't require bodily presence, and then you'd have the same problem as with normal browser play). And that means there would be lots of things irrelevant to the game itself (surroundings), so you'd be adding stuff that necessarily annoys some people and makes the client hard to make and less attractive at the same time. "Harder to make" could be circumvented by taking an existing platform (second life?), but then there would be even more extra-game stuff going on. Then on the other hand, it could attract a completely new player clientele; from what I've seen, generic virtual worlds tend to be surprisinly barren and primitive when it comes to actual game content (so a board game might actually be from the more exciting end).

yakago wrote 4 years ago:

VR headsets would be much too inconvenient to be used.
And at the point that they do become convenient, you can probably cheat again :)

antti wrote 4 years ago:

Yakago, have you tried Oculus Quest? In my opinion it would not be so inconvenient. Sure, taking the device out from wherever you are storing it and then putting it on takes a bit of time, but once you have it on I find the controls slick enough. I can see that non-gaming-savvy players could have trouble with it, though (not implying that you are one of those).

As for the cheating part, the Oculus definitely doesn’t prevent it; you might, for example, be operating an iPad with Master of Go in your lap while playing. Although, newer devices (Quest included) seem to have finger-tracking features which could maybe be employed to detect suspicious activity.

Of course, if you really want to cheat you can just put headphones on and have a friend tell you where to play – without a proctor, I cannot see how this could be prevented. One player actually even tried this in the Korean professional qualification tournament, but that did not work out well.

yakago wrote 4 years ago:

My experience is from an Oculus Rift S, which I assume is a bit heavier than the Quest?
But I mean for me, the headset is really warm, it is more straining on the eyes, and in general I feel a bit worn out after VR use.
Plus the addition of actually having to own a headset, but that could be less of an issue in the future.

Maybe there's a sweet spot, but I'm a bit pessimistic in terms of what kind of comfort people would give up to play go online =)

antti wrote 4 years ago:

The warm-ness is actually a fair point. In Finland I did not have trouble wearing the headset for 60 minutes at a time, but in Japan in the summer even 30 minutes made me sweat bullets.

Probably a (well made) go app would not be as hardware-intensive as speedier games, and might not make the device run quite as hot, but certainly the user experience is still a lot worse than playing on a real board.

MarcelGruenauer wrote 4 years ago:


this is a very interesting topic; it is also being discussed on L19. There I've posted the idea of "proxy tournaments". Please see

What do you think about this?

(I don't know whether it is better to continue the discussion here or on L19, where there are potentially more and, appropriate for the topic, globally more diversified, participants.)


antti wrote 4 years ago:

Now that we have entered the coronavirus era, and will hopefully soon be in the post-coronavirus era, there should definitely be a market for proxy tournaments. It can make sense both financially and ecologically, and should also help support local go clubs – of which there should also be more demand now that online cheating is becoming rampant.

I’m thinking that the Pandanet Go European Team Championship could also do well as a proctored two-weekend tournament. While some players would need to travel inside their countries, in exchange the finals would no longer have to be hosted at the European Go Congress, and any possible cheating issues would be solved.