Logic Masters Deutschland e.V.

I made this puzzle following Scojo's prompt to use negator modifiers along with sandwich clues.

• Normal sudoku rules apply.
• Divide the grid into two orthogonally connected regions such that no 2x2 area is completely contained in a region. All cells in one region will have a value -D, where D is the digit on the cell, and all cells in the other region will have a value of D.
• Cells marked with a circle contain a digit equal to the count of the other (up to 8) neighboring cells that are in the same region.
• Cells marked with a square contain a digit equal to the count of the (up to 8) neighboring cells that are in the other region.
• Clues outside the grid show the value sum of all cells strictly in between the digits 1 and 9 in the direction of the row/column of the clue.
• Along a dark teal line any three consecutive cells have values in different residue classes modulo 3.
• Cells joined by a dark teal dot have values in the same residue class modulo 3. Not all possible dots are given.

Online in Sudokupad

Note: The residue classes modulo 3 are

• [0] = {⋯, -9, -6, -3, 0, 3, 6, 9, ⋯}
• [1] = {⋯, -8, -5, -2, 1, 4, 7, ⋯}
• [2] = {⋯, -7, -4, -1, 2, 5, 8, ⋯}

See also:

• not a drip, got gallons
• absolute anihilation
• obezyanka nol
• null lol