Heyawake is a binary-determination logic puzzle published by what Japanese publisher that specializes in games, and especially, logic puzzles?
Nikoli (publisher) Nikoli Co., Ltd. (Japanese: 株式会社ニコリ , Hepburn: Kabushiki-gaisha , Nikori) is a Japanese publisher that specializes in games and, especially, logic puzzles. "Nikoli" is also the nickname of a quarterly magazine (whose full name is "Puzzle Communication Nikoli") issued by the company in Tokyo. "Nikoli" was established in 1980 and became prominent worldwide with the popularity of "Sudoku".
Yajilin Yajilin (ヤジリン) is a type of logic puzzle published by Nikoli. It has been published in English under the name "Arrow Ring", such as in the 2005 U.S. qualifier for the World Puzzle Championship.