https://www.funwithpuzzles.com/2014/01/online-diagonal-sudoku.html
Online Diagonal Sudoku (Logical Thinking Sudoku Variation)
In Sudoku X you will be given a 9x9 grid, which is evenly divided into 9 squares. Your goal in the game is to put numbers 1 to 9 onto the blanks.
diagonal sudokulogical thinkingonlinevariation
https://dordle.io/the-daily-diagonal-sudoku
The Daily Diagonal Sudoku
Conquer tricky diagonals in the exciting entertaining game, The Daily Diagonal Sudoku, and earn the most impressive achievements every day!
the dailydiagonal sudoku