Logic Masters Deutschland e.V.

That darn cat got in the yarn again! Now all the bits and bobs are scattered about. Sigh.

Sudoku: Normal Sudoku rules apply; place the digits 1-9 once in every row, column, and 3x3 box.

Bits and Bobs Cell: There exist 9 BB Cells in the grid such that there is exactly one BB Cell in each row, column, and 3x3 box. Digits of BB Cells do not repeat. A BB Cell is the center of a 3x3 zone where the value of each cell is doubled; cells can be affected by more than one zone and therefore can be doubled more than once. For example, if r3c3, r4c4, and r5c2 are BB Cells, the value of r4c3 is doubled three times and the values of r4c2 and r5c3 are doubled twice. It is up to the solver to determine the position of each BB Cell and its zone.

Balls of Yarn: Values along a strand of yarn sum to the value in its connected ball.

Expected Difficulty: 4 stars

Many thanks to Marty Sears for help with the graphics, as well as Ul-Rhymm, Jenny, Matt_Y_Ddraig, and gdc for testing.

If the colors bother you, or if you're uncertain about whether a cell is visited by the yarn, a traditional version of the puzzle can be found here.

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