Rules:
Place the digits 1-9 once each into every row, column, and box.
There are 2 portals that each connect opposite sides of the grid. The orange portal connects R1C5 and R9C5, while the blue portal connects R5C1 and R5C9.
For each house draw 3 lines starting at that house and ending at different utilities, for a total of 9 lines. Lines move orthogonally throughout the grid. With the exception of houses and utilities, multiple lines cannot contain the same cell. Lines cannot pass through cells containing a tree.
Lines that end at the Telephone Utility (phone) are telephone lines. Adjacent digits along a telephone line differ by no more than 2.
Lines that end at the Water Utility (water drop) are water lines. Adjacent digits along a water line differ by at least 5.
Lines that end at the Power Utility (lightning) are power lines. Digits along a power line alternate between even and odd.
Digits in cells containing trees do not repeat.
Have fun solving!
Solution code: Column 8 from top to bottom
on 6. February 2026, 16:07 by baltoguy
Loved it! Note: Be sure to understand Rule #1 before you move on to the rest. I would add "for the purposes of the lines, the portals . . ." But maybe experienced solvers already know that.
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