# Hexagonal Nurikabe

Nurikabe is a popular grid puzzle, usually played on a square grid. Here is my attempt to adapt it to a hexagonal grid.
To solve it, you must shade cells in the grid such that these conditions are met:

• Like regular Nurikabe, each region of unshaded cells must contain exactly one number, which is equal to the size of the region. (numbered cells can never be shaded)
• All shaded cells must form a continuous region
• Three shaded cells must not form a closed triangle (i.e. Three cells around a vertex must not all be shaded)

Here it is in text form if you prefer

             __
__/  \__
__/ 2\__/  \__
__/  \__/  \__/  \__
__/  \__/  \__/  \__/  \__
/  \__/  \__/ 2\__/  \__/ 4\
\__/ 1\__/  \__/  \__/  \__/
/  \__/  \__/  \__/  \__/  \
\__/  \__/  \__/  \__/  \__/
/  \__/  \__/  \__/  \__/  \
\__/  \__/  \__/  \__/  \__/
/  \__/  \__/  \__/  \__/  \
\__/ 3\__/  \__/13\__/  \__/
/  \__/  \__/  \__/  \__/  \
\__/  \__/  \__/  \__/ 7\__/
\__/  \__/  \__/  \__/
\__/  \__/  \__/
\__/  \__/
\__/


• Nice idea, and the example shows the puzzle has good potential! Nov 30, 2020 at 18:46
• I think this might have been created by Nikoli under the name Atsumari: en.wikipedia.org/wiki/Atsumari The only difference is that they restrict the sea ('shaded area') to disallow pools of 7 hexagons, whereas you exclude pools of 3. Jan 9 at 21:17
• @AdriaanKoster Interesting, they also introduce the "0" cells which are always black. Excluding pools of 3 is a more direct conversion from standard square grid rules. Jan 9 at 22:09

## 1 Answer

To start, we can

immediately close the 1 in. This gives us this much:

And now the 2s are completed; the unshaded cell on the left must be grabbed by the 3, so we can complete that too.

Next,

The 4 at the top right can't join up with the unshaded region close to it, so we need to put a wall between them.

The big clump of shaded cells that have already been placed can't be blocked off -- so the isolated unshaded cell must go with the 7.

And finally, making sure rooms don't touch:

we can close off the 4 room, then the 7 room, and then...

...by counting hexes, we have to shade one more cell.

And the puzzle is solved! The solution:

• Very good! I hadn't made any Nurikabe puzzles before, but I've been thinking about using this different grid system for a while. I hope it was enjoyable! Nov 29, 2020 at 23:13
• @MatthewJensen It was! Not too difficult, but it was neat to see how the hex grid affected region shapes.
– Deusovi
Nov 29, 2020 at 23:21