Author/Opus: This is the 164th puzzle from our contributing puzzlemaster Serkan Yürekli.
Rules: Variation of Kakuro. The gray (2×2) cells are to be filled by a single digit which sits in multiple rows and columns. No digits can repeat within an entry, regardless of if it is in a small or large cell.
Answer String: Enter the values in each white/gray cell in the marked rows from left to right, separating the groups with a comma.
Time Standards (highlight to view): Grandmaster = 3:00, Master = 4:15, Expert = 8:30