Shade two cells in each thickly outlined region, so that each shaded cell shares an edge with exactly one other shaded cell.
(Rules and example from WPC 2017/Round 13)
History of the puzzle
First appeared on Nikoli vol 124 (2008). Invented by 湾狼子. The name refers to nori, seaweed used in Japanese cuisine.
Appearances in the past WPCs
- WPC 2017/Round 13 by Swaroop Guggilam