Corral

Corral, also called Bag or Cave, is a path-drawing logic puzzle in which solvers must fill in a loop along the perimeters of cells in a grid so that numbered clues properly indicate the number of cells visible from their position.

Background
Corral first appeared in Puzzle Communication Nikoli, volume 60. The genre was invented by ゲサク ("Gesaku") with the title of バッグ, which means "bag". The genre was originally presented as a loop puzzle.

Closely related genres to Corral include Kurodoko (instead of a loop, shade squares in a "dynasty" formation instead) and Canal View.

Puzzle Application
Corral puzzles are usually presented fairly minimally, usually only as a blank grid with some cells containing numbers. The goal of the puzzle is to create a 'corral' that contains all numbered cells and satisfies the constraints set by them.

The rules for solving a corral are as follows:


 * The perimeter of the "corral" must be continuous. No breaks, no crossing.
 * Numbers indicate the number of cells a particular can "see", in each of the cardinal directions, including the cell they are on.
 * All numbers must be inside the 'corral'.

Visually, a Corral puzzle may appear very similar to a Slitherlink puzzle. A good way to tell them apart is that Slitherlinks can only contain number 0-3, while Corral can have any number from 2 to the sum of the dimensions of the grid minus 1.

Examples

 * - Like the title says, this was a logic puzzle chimera, combining two genres into one. In this case, the given puzzle can be solved both as a Corral puzzle and a Nurikabe. While they don't interact during solving, the fact that the grid serves a dual purpose is unique.
 * - The meta for the Cactus Canyon round, this puzzle combined answer-placement and a Corral puzzle. Numbers in the grid serve two purposes: they can be used to solve the Corral puzzle, but can also be used to place the answers. Each number is the centerpoint for an answer, where that answer can be placed in reading order within all of the cells visible by that number.