Hitori Hitori is played with a grid of squares or cells, with each cell initially containing a number. The objective is to eliminate numbers by blacking out some of the squares until no row or column has more than one occurrence of a given number. Additionally, black cells cannot be adjacent, although they can be diagonal to one another. The remaining numbered cells must be all connected to each other. Slitherlink Slitherlink is a logic puzzle is played on a rectangular lattice of dots. Some of the squares formed by the dots have numbers inside them. The objective is to connect horizontally and vertically adjacent dots so that the lines form a simple loop with no loose ends. In addition, the number inside a square represents how many of its four sides are segments in the loop. Numbricks Numbricks puzzles are similar to Hidato. The most important difference is that it is only possible to move 1 node left, right, up, or down. It is played on a rectangular grid of squares. Some of the cells have numbers in them. The object is to fill in the missing numbers, in sequential order, going horizontally and vertically only. Diagonal paths are not allowed. Suguru Suguru, also known as Tectonics or Number Blocks, is a Japanese puzzle invented by Naoki Inaba. The goal is to fill a given rectangular grid with numbers, so that every designated area contains a sequence of non-repeating, consecutive numbers, starting from 1 and going up. Also, adjacent (touching) cells should not contain the same number, even diagonally.