Logic Masters Deutschland e.V.

Rules:

Normal sudoku rules apply.

Draw some region sum lines into the grid. The sum of the digits on a line is the same within each box. In this puzzle, a region sum line also does not contain repeated digits.

Region sum lines move orthogonally from cell to cell and must enter at least two 3x3 regions. Region sum lines do not branch, overlap or touch themselves or each other orthogonally. They may, however, touch themselves or each other diagonally.

Clues outside the grid are j-sums clues. They give the sum(s) of groups of contiguous region sum line cells within their row or column. The sums within a clue appear in the correct order left to right/top to bottom. Where given, clues are complete, i.e. if there are 2 j-sums clues, there are exactly 2 contiguous groups of region sum line cells.

A ? clue is an unspecified (non-zero) single digit number, and a ?? clue is an unspecified double digit number (that is, no leading zero). An * could be a single or double digit clue.

The cell in the center of the grid is either a maximum or minimum cell, i.e. the digit in that cell is either larger or smaller than all of its orthogonally adjacent neighbouring digits.

Below is an example 6x6 puzzle with the same rules (minus the max/min rule). I recommend starting with it if you are new to region sum lines and/or j-sums.

Below are the links the the 6x6 Example puzzle and the 9x9 main puzzle in Sudoku-Pad. Have fun and please consider rating and commenting if you enjoyed :)

Example Puzzle (6x6)

Some Sums (9x9)