Theme: Two Gates (Originally for 2016 Arlington Puzzle Festival as playoff puzzle)
Author/Opus: This is the 260th puzzle from Thomas Snyder, aka Dr. Sudoku.
Rules: Standard Sudoku rules.
Answer String: Enter the 1st row from left to right, followed by a comma, followed by the 9th row from left to right.
Time Standards (highlight to view): Grandmaster = 2:30, Master = 4:15, Expert = 8:30