Category:Hidden categories
From The Blockheads Wiki
Hidden categories do not appear in the list of categories at the bottom of the page, unless the "Show hidden categories" preference is checked, which is not available to readers.
A category is marked as hidden by putting the __HIDDENCAT__
magic word on the category page. It is automatically added to this category.
Maintenance categories, especially those that contain articles, should generally be here as they're only useful to editors.
Subcategories
This category has the following 5 subcategories, out of 5 total.