Elimination rengo

I have played this variant a few times on a real board. The new “casual rengo” mode on OGS seems particularly suited for it.


  • 2 teams of players;
  • one teacher, who will not play but will watch the game.

The team is played like a standard rengo game, but with the following additional rules:

  • after a player makes a move, the teacher may say “this is a bad move, you get a yellow card” or “this is a very bad move, you get a red card”;
  • if a player gets a red card, they are immediately eliminated from the game;
  • if a player gets a yellow card for the second time, they are eliminated from the game;
  • what constitutes a good, bad or very bad move should be decided relative to the rank of the player;
  • if a player plays a very good move (relative to their rank), the teacher may exceptionally award them an “extra life”, which will cancel the next “yellow card” for that player;
  • if a team runs out of players, that team loses the game.

I suppose the teacher could use an AI to help them, although the teacher should only penalise mistakes relative to the players’ ranks. Ideally the teacher should be at least three stones stronger than the strongest player.


It could be interesting as a particular way to study.

Probably the more often the AI is used, the more it becomes a bit like “guess the ai move here”. However it might also be a bit more objective than a human teacher kind of refereeing the game.

It might work better between friends, but I can imagine disagreements over yellow and red cards :slight_smile:


No, a “bad move” should be relative to a player’s rank and prior knowledge. It shouldn’t just be “the AI would have played something else”.

What disagreements? The yellow and red cards are decided by the teacher. The players don’t get to disagree.

But humans tend to disagree. If you watch different sports (soccer would have a lot of coverage), people tend to disagree with referees giving yellow and red cards :slight_smile:

I know you mentioned that, but I’m just thinking in practice, let me use Katago while refereeing a game of players 3 or more ranks lower, and it might be tough to decide what is bad relative to their level. One could try do that with katago’s score loss but which is useful to say what is and isn’t a mistake and how big, but not so useful to say if it’s a 10kyu mistake or a 15kyu mistake etc. What is easy to do is say “that’s not the ai move and it loses 6 points” :slight_smile:

It was just some observations. It could be a fun idea to try out :slight_smile:

I’ve played this at teaching events with Guo Juan 5p as referee. I think you need an experienced teacher like her, trying to use AI won’t help. It’s fairly lighthearted, usually after dinner with alcohol.


Does the referee explain the reason for giving a card?

When I read the title, I was expecting something else: a multi-round rengo tournament where the winning team of the previous round gets split into two opposing teams for the next round. Then the winner of the final round (1 vs. 1 game) wins the whole tournament.

That actually sounds like a great idea! You should set up a tournament like this here on ogs :slight_smile:

1 Like

Sometimes they do.

Sometimes they don’t, because the explanation would be “this move is bad because the opponent can punish it by playing there” and the teacher doesn’t want to tell the opponent where to play.

I’ve also had a teacher who said "This is a mistake, but I’ll wait a few moves before giving a yellow card. If the opponent successfully punishes the mistake, I’ll give you a yellow card; if the opponent fails to punish you and the sequence becomes good for you, I’ll give them a yellow card instead.

1 Like