Logic Masters Deutschland e.V.

This is a Fog of War puzzle. You can play it on SudokuPad: https://sudokupad.app/mpe2ooykxw

Rules: Normal Sudoku rules apply. Dots: Some dots are marked inside boxes, each touching 2 or 4 digits. Two such sets of digits have equal sums if and only if the corresponding dots belong to the same box — that is, within a single box, all dot sums are equal, and between boxes, the dot sums differ. Dynamic fog of war: The grid is partially covered in fog. Entering correct digits may clear some fog (not necessarily beneath or around the entered digit). No guessing is required.