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Theme: No 2×2 White Blocks
Author/Opus: This is the 5th puzzle from guest contributor Jamie Hargrove.
Rules: Shade some cells black so that all unshaded number and arrow clues indicate the exact count of shaded cells in the given direction. Shaded cells cannot share an edge, and all white cells must remain connected as part of a single contiguous group. It is allowed to shade over some of the numbered cells; a shaded over clue may or may not be true. Also, as an extra rule from standard Yajisan Kazusan, there cannot be any fully unshaded 2×2 cell blocks in the grid.
Answer String: For each row from top to bottom, enter the number of shaded cells as a single string.
Time Standards (highlight to view): Grandmaster = 5:00, Master = 12:00, Expert = 24:00
Note: Follow this link for other less common Shading puzzles.