Suguru Puzzles - 200 Hard to Very Hard Puzzles 12x12 vol.16

Suguru, also known as Tectonics or Number Blocks, is a Japanese puzzle invented by Naoki Inaba. The task consists of a rectangular or square grid divided into regions. Each region must be filled with each of the digits from 1 to the number of cells in the region.Also, adjacent (touching) cells should not contain the same number, even diagonally.