Rogue Fantasy Castle

kul ja

They can still ask for payment to access it. You can just do whatever you want with it after you get it.

Public Domain refers to works that are not protected by copyright law. Meaning they belong to the public and can be used in any way without permission of the author.

This means you may sell access to the work (but you may not enforce any license to use the work), make copies, distribute, alter, archive, and display them at will.

Derivatives of the public domain work may still fall under Copyright, to the extent that they are modified. (For example, the example images shown here may NOT be public domain themselves)

Laws regarding the transactional nature of accessing the work are likely to still apply, so it is inadvisable to simply screen-capture this page.

Similarly you also may not falsely claim original authorship of the work legally, though it is somewhat dubious what repercussions would arise from doing so.

Edit to add: There is nothing that prevents anyone from attempting to drag you to court over a public domain work. They may not have legal standing to do so, but sometimes causing you the hassle of court is a win for them already.

Edit2: US Copyright law version of Public Domain. Every country has their own unique copyright laws which may differ from each other. CC0 (Creative Commons Zero) is a formal license that applies these same properties as a matter of contractual license, in order to be valid in countries where Public Domain would not normally apply. Each country's Public Domain, should they have one, takes precedence if it is the country of publication.