This puzzle style, originally published by Nikoli, was part of our first Loop Variety Collection.
or solve online (using our beta test of Penpa-Edit tools; in default lineox mode: left-click+drag draws line, clicking one time in a cell marks a circle and a second time marks an X)
Theme: 2 Many 2×2’s
Author/Opus: This is the 2nd puzzle from guest contributor Martin Ender.
Rules: Draw a single, non-intersecting loop in the grid that enters and exits each bold region exactly once. If a number clue is given in a region, that number indicates the exact number of cells used by the loop in the region. Unused cells cannot be orthogonally adjacent across different regions.
Also, see this example:
Difficulty: 3.5 stars
Time Standards (highlight to view): Grandmaster = 5:15, Master = 8:15, Expert = 16:30