PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a shading mode and a composite mode where left click inside cell shades square, left click + drag draws line segment, right click inside cell adds dot, and right click on cell edge adds an x.)

Theme: Foursomes

Author/Opus: This is the 363rd puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Cross the Streams rules. Also, the shaded region must be able to be split into tetrominoes to form a valid LITS solution (meaning all tetrominoes are connected but no two tetrominoes sharing an edge are the same shape, including rotations and reflections).

Difficulty: 4 stars

Time Standards (highlight to view): Grandmaster = 5:45, Master = 11:00, Expert = 22:00

Solution: PDF; a solution video is also available here.

Note: Follow this link for other Cross the Streams. If you are new to this puzzle type, here are our easiest Cross the Streams to get started on.