If you read the book you surely know something about Cyvasse, the game that looks like chess from Old Volantis. Its rules are not been officially released or explained in the books by Martin yet, but there are several unofficial version you can find (print) and play.
I always wanted to try it out, but I literally lost among all the different versions I found. Did you ever try it and have a favourite version?
Here some links with the best versions I found online, starting from my favourite one:
1) https://www.cyvasse.io/
You can play this version of the game online, with computer or with another opponent.
2) https://gameofcyvasse.com/
Just nice alternative rules and printable cool units.
3) https://cyvasse-online.com/rule_sets/mikelepage
Another good version of the rules.
4) https://www.thingiverse.com/thing:92172
Best printed version of the game I've ever seen, you can find another version of the rules in this link.
There are even some apps for Android devices, but I really didn't like them for many reasons (no player vs computer option, strange rules, etc.).
I always wanted to try it out, but I literally lost among all the different versions I found. Did you ever try it and have a favourite version?
Here some links with the best versions I found online, starting from my favourite one:
1) https://www.cyvasse.io/
You can play this version of the game online, with computer or with another opponent.
2) https://gameofcyvasse.com/
Just nice alternative rules and printable cool units.
3) https://cyvasse-online.com/rule_sets/mikelepage
Another good version of the rules.
4) https://www.thingiverse.com/thing:92172
Best printed version of the game I've ever seen, you can find another version of the rules in this link.
There are even some apps for Android devices, but I really didn't like them for many reasons (no player vs computer option, strange rules, etc.).