Some have guidelines about how much time to spend on social situations, while others go with the flow without any plan ahead of time. An hourglass tracks time without being disruptive, requiring one to notice that the flow of sand has ended. This puzzle includes an hourglass shape made of a Near Neighbor line. These are three completely-unrelated facts.
Rules:
Normal Sudoku rules apply.
Adjacent digits on red/pink lines differ by at most two.
Cells separated by a white dot contain consecutive digits. In cells separated by a black dot, one digit is double the other. Not all possible dots are given.
Estimated difficulty: 2.5 out of 5
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