This is a Zendo-type game, where the koans are go-positions. The goal is to guess the rule which separates the green boards from the red boards. Anyone may submit a new board, which I will then classify as green or red, or guess a rule, which I will confirm as correct or provide a counterexample to. There is no winner, think of it more as solving a puzzle collaboratively (publicly discussing ideas and working together is encouraged).
Valid koans for this first game are legal positions on a 5x5-board, meaning any position where each chain has at least 1 liberty. The rule does not use any go knowledge apart from the basic definitions of chains (solidly connected groups of stones of one color) and liberties. The rule also does not use the orientation of the board, meaning that any green board rotated or mirrored will still be green, and same for red boards.
Some examples of possible rules (none of them correct for this game of course):
“There are more black stones than white stones”
“All chains contain exactly 2 stones”
“The number of white stones is the same as the number of empty intersections”
“All empty intersections are in the same connected area (i. e. if they were stones they would form a single chain)”
“Each chain is adjacent to exactly 1 chain of the other color”
For each rule, the green boards would be those following the rule, and the red boards those not following the rule.
You can submit boards in any format you like, but preferably using this tool: https://rubymineshaft.github.io/
I’ll start you off with 4 boards of each type, and add new boards here as they are submitted:
Green boards
Red boards
The first rule was quickly quessed by @KAOSkonfused
Spoiler for first game
The rule was: If all the stones were the same color, they would form a single connected chain.
Jump to the start of subsequent games:
Second game by le_4TC
Third game by Sanonius
Fourth game by martin3141
Fifth game by RubyMineshaft
Sixth game by Vsotvep
Seventh game by martin3141
Eighth game by le_4TC
Ninth game by RubyMineshaft
Tenth game by martin3141
Eleventh game by Vsotvep
Twelfth game by Feijoa
Thirteenth game by Jon Ko
Fourteenth game by yebellz
Fifteenth game by Vsotvep
Sixteenth game by Maharani
Seventeenth game by ArsenLapin1