Logic Masters Deutschland e.V.

there are nine doubler cells in this puzzle: one in every row, column, and 3x3 box. digits in doubler cells form a complete set of the digits from one to nine (i.e. they cannot repeat). the value of a doubler cell is twice the digit within that cell.

cells separated by a black dot have values that are in a 1:2 ratio (i.e. one value is twice the other). cells along a little killer diagonal have values that add up to the indicated total (always 33). not all black dots or diagonals are necessarily given.

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