The Block Tool

The Block Tool in Crossword Wrangler is used to toggle individual cells between open and blocked in order to set the beginning and end of lights within the crossword grid.

This tool is useful when creating US-style crossword puzzles, where there is generally a greater degree of checking than is typical of UK-style grids. Normally one begins with an all open initial grid (see Creating a new grid) then selectively blocks cells to define the structure of the puzzle, though the tool can work perfectly well in conjunction with other tools.

However, it is possible to achieve the same results using the Light Tool or a combination of the two. Indeed, while it is uncommon for crosswords to feature a mix of blocks and bars, it is perfectly valid to do so using the Bar Tool and/or the Light Tool.

Using the Block Tool

1. In the tool strip, select the Block Tool icon:

2. Click on the cell you want to toggle between open and blocked:

Note that new lights 12 Across and 14 Down have been implicitly created.

Symmetry

The Block Tool also respects the grid’s symmetry settings. When symmetry is enabled, toggling a cell on or off will toggle its symmetric counterparts likewise, ensuring the overall symmetry of the grid is maintained. For example, with reflection about both diagonals enabled, one click on an open cell can create up to four blocked cells simultaneously:

Creating open cells

Bars

Because grids with both blocks and bars are uncommon, when the block tool opens a blocked cell, it will be created without any surrounding bars. This may implicitly add new or amend existing lights. Starting with this configuration:

Clicking on the cell in the centre using the block tool will open it without adding any bars and will implicitly create new lights passing through the newly opened cell:

Single open cells

Opening a cell inside a blocked region can produce single open cells:

Because lights are defined as continuous series of at least two open cells, a single open cell does not constitute a light on its own. It may, however, become part of a light if adjacent cells are subsequently opened.