Logic Masters Deutschland e.V.

Normal sudoku rules apply.

Additionally there are 9 snakes hiding in the grid, each containing 9 orthogonally connected cells. The end of the first snake connects with the start of the next such that all 9 snakes form a single chain without looping. The cells that connect the end of one snake to the start of the next are marked with cages. The snakes may touch themselves and each other.

Each snake should start at 1 and form a string of orthogonally connected digits in numerical sequence (123456789) BUT grey coloured cells are wrong in regard to the snakes and do not display their correct digit. (Eg. If the 3rd cell of a snake is grey the digit placed there must not be 3 but can be any other digit.)

Cells with grey circles contain odd digits. Cells with grey squares contain even digits.

Visual example of the ruleset:

f-puzzles link