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Sam T wrote on 2021-03-15 UTCExcellent ★★★★★

I have, as per Freeling’s comment, made a number of variants to Congo to address the issues brought up:

  • To address the fact Congo looks drawish, I have adopted the “Ko Rule” in my variant: Someone who repeats a previous position in a game loses. This eliminates draws.
  • To address the issue with river drownings making attacks harder, I have made the A, B, F, and G files of the rivers have “islands”: While the crocodile can move like normal on these squares, other pieces will not drown.
  • I have made the pawns stronger: A pawn can not retreat until it is promoted on the 7th rank; on the other hand, pawns across the river can now move and capture sideways. A promoted pawn is more powerful: It can move or capture to any space one or two squares away (like Chess, a promoted pawn should win unless it can be recaptured quickly)
  • I have made the elephants able to move forward like a Shogi Lance. They can also only move backwards one square.
  • I have changed the opening setup from GMELECZ to ZCELECZ, removing the Monkey and Giraffe, and having a second Zebra (Knight) and Crocodile. This way, the game can be played with an ordinary chess board and pieces.

In my Zillions-vs-Zillions testing, the games are never draws, and Black wins more often once we give Zillions 30 or more seconds to think through a move.

My changes can be seen here:

Look in the folder “Congo”. Full rules for this variant, along with multiple possible opening setups, is here:

Out of respect for the copyright included with the Zillions implementation of Congo, I am not distributing a modified version of the Congo zrf. Instead, I am distributing the original version, along with a Linux/Cygwin script to change Congo to have another .zrf with the modified rules. I have also made from scratch board artwork representing the new river with islands.

(Admin: This is Sam Trenholme. If you have a chance, please update my email address to be “pbm” in the domain “” so I can reset my password).

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