Puzzle 1: “Easy as 1-2-3”
Place some additional black and white stones on the board such that:
- Each stone with a number on it belongs to a chain of that size.
- Each chain has exactly 2 liberties.
- No 2×2 region is entirely black or entirely white.
Interactive board
(I recommend opening the sgf in an editor such as Sabaki, then you can add stones with the edit tool and the existing labels will not disappear)
Puzzle 2: “Odd vs even”
Same rules as Puzzle 1.
Interactive board
Puzzle 3: “Online Go” (Kropki sudoku)
- Place the digits 1-9 in every row, column and 3×3 box.
- Digits separated by a black dot have a 1:2 ratio.
- Digits separated by a white dot have a difference of 1.
(Not all possible dots are given.)
Play it here!
