Hexagonal Grid

Hexagonal grids are a type of alternate grid shape for puzzles, in which square cells are swapped out for hexagonal ones, tessellating across a particular space. These grids add a new dimension to the puzzles they're featured in, allowing things to run horizontally as well as on one of the two diagonals.

Puzzle Application
Compared to square grids, hex grids have an extra direction of travel for their contents, allowing items to be entered or read either horizontally or vertically (depending on the rotation of the hexagons), as well as along two diagonals. This allows for an extra 'dimension' to be added to puzzles without resorting to 3-dimensional structures. In a similar vein, it also means that every cell in a hex grid is checked three times rather than the usual two.

Hexagonal grids are primarily used for crosswords and logic puzzles, albeit usually as one-off gimmicks. Only a select few types of puzzles tend to use hexagonal grids by default or as a common variation, such as Rows Gardens and certain variations on Regex Crosswords.

Examples

 * - A Regex Crossword (the first one to show up in the MIT Mystery Hunt) that just happens to take place on a hexagonal grid. Whether this was an attempt to make the puzzle easier or harder is unknown.
 * - Somewhat of a logic-crossword hybrid, in which solvers are given a size-7 hex grid and several clues as to how to enter answers within the grid (via paths taken by rovers and some entries between corners).
 * - Puzzle 7 within this puzzle was a hex-grid version of a Tents logic puzzle, with clues on the edges going in one of three directions.