Nikoli Puzzles
What makes Nikoli puzzles unique is that our editors collaborate with individual puzzle creators and fans. You just need an open mind, thinking for yourself that “Maybe this is the right way”
A unique aspect of Nikoli puzzles is that a puzzle that is challenging to a beginner and yet solvable, can also give the expert solver pleasure in solving it. Then there is the new generation, young people becoming Nikoli fans by discovering the puzzles on the bookshelves of their parents.
Source: nikoli.co.jp