Normal sudoku rules apply. Any three consecutive digits on a red modular line must have different remainders when divided by 3. A clue outside the grid gives the sum of the digits on the marked diagonal. Digits may repeat on a diagonal where allowed by other rules. Digits on the grey circles sum to a factor of 2023, and digits on the grey line sum to a multiple of 8. It is up to the solver to deduce these sums.