Hello, I was looking through sensei's library for any articles about Zengo, and I saw none, so I was wondering if perhaps it had an alternate more common name.
For those of you who don't know, Zengo is a little like rengo, but with an odd number of players, usually three or five. People take turns playing moves, and because there is an odd number of them, they will alternate between black and white. This style of playing teaches people the habit of not only analysing your opponent's pieces but your own pieces as well.
Looks like an article for it has already been made, apparently there is a space between zen and go, so it did not show up when I searched Senseis for zengo. You can find that article here, I added a link to it from the go variants page. Zen Go