Logic Masters Deutschland e.V.

Regular sudoku rules apply. A single slitherlink loop must be drawn around the sudoku grid. ALL instances of 1, 2, and 3 in the grid serve as slitherlink clues (aka. cells containing 1,2, and 3 must have x number of line segments adjacent to it with x being the number in the cell). Like a regular slitherlink loop, the loop drawn around this grid may not touch itself or cross at any point. The black lines in the grid indicate parts of the loop that have already been placed.

In addition, XV Sudoku rules apply to this grid. Diamonds have been placed in the grid where the cells directly adjacent to them sum to 10 (X) or 5 (V). If the digits next to a diamond sum to 5 (V), the loop MUST pass through the diamond. If the sum of the digits is 10 (X), they act as an X would in a slitherlink puzzle, and the slitherlink loop does NOT pass through them. Note that there is a negative constraint: cells that don’t have a diamond between them do not sum to 5 or 10.

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