Normal sudoku rules apply. Digits in cages add up to the small clue in the top left corner of the cage, if given. Digits cannot repeat within a cage. The main diagonal (in blue) must include the digits from 1 to 9 once each. Digits within the white circles must appear at least once in the four cells touching the circle. Digits along an arrow sum to the digit in that arrow’s circle. The two digits on the two-cell-palindrome grey line must be the same. The cell with the grey square must contain an even digit. Cells separated by an X must contain digits that sum to 10. Black dots separate cells containing digits with a ratio of 1:2. White dots separate cells containing consecutive digits.