Catch the Zippersnake
- Kropki dots
- XV and number dots
The brief
- Normal sudoku rules apply.
- Draw a snake that starts and ends at a purple spot and has a purple spot exactly at its centre. The snake can only move orthogonally from cell to cell, and may not touch itself, not even diagonally.
- The snake functions as a zipper line; any pair of digits that are an equal distance from the central spot sum to the digit on that central spot.
- Any pair of cells connected by a clue (dot, diamond, X or V) must either both be on the snake, or both be off the snake.
- Cells connected by a white dot are consecutive.
- Cells connected by black dot are in a 1:2 ratio (one is double the other.)
- Cells connected by a green dot must have a difference of at least 5.
- Cells connected by red diamond have the same parity (they're both odd or both even.)
- Cells connected by an X sum to 10.
- Cells connected by a V sum to 5.