Logic Masters Deutschland e.V.

Rules:

• Normal sudoku rules apply.
• Arrow: Digits along arrows sum to the digit in that arrow's circle.
• Quadruples: Digits in the clued circles must appear in one of the 4 adjacent cells.
• Magic square: The central 3x3 box (highlighted yellow) is a magic square (ie, the rows, columns, and main diagonals in that box each sum to the same number).
• However, one of the digits 1-9 (which the solver must determine) cannot be in an arrow circle, does not contribute to the sum along arrow lines, and cannot appear in one of the 4 cells adjacent to circled clues (regardless of what the clued digits are). That digit behaves normally in the magic square.

F-puzzles: https://f-puzzles.com/?id=y8g9vnlq

CTC app: https://tinyurl.com/3t6cfbmw

Note: Because of the puzzle's rule set, some correctly placed digits may be flagged as incorrect if solved using the above software.