Using DnD monsters in fiction writing - what’s the laws for/against?
<p>If I wanted to use a Gelatinous Cube/Jubilex in a (hopefully one day published) fictional story, could I do that, or is there some copyright against it? I wouldn’t be using media or actual descriptions per se, mainly just the names of the creatures to identify what the thing was. I want to be sure before I actually write the thing.</p>

<p>Copyright does not protect ideas, but it does protect expressions of ideas. The idea of a creature looking like a cue of gelatin, that can surround and devour prey is not protected, but the specific description is protected by copyright. You may not use that description, or closely paraphrase it, without permission. If you do, that is copyright infringement.</p>
<p>In addition, one may not create a derivative work, that is a new work &quot;based on&quot; an existing (source) work, without permission (assuming the source is still in copyright). Imitating one monster is probably not enough to make the new work derivative. But if several monsters or characters are used, and their  detailed point-by-point characteristics are imitated, that could well be enough. Using a recognizable major character from a previous works as the protagonist or as a major character will make the new work derivative. Using a clear and detailed setting from a prior work can also make the new work derivative, say setting a story in Minas Tirith from <em>The Lord of the Rings</em> or Los Eisliy Port from <em>Star Wars</em>.</p>
<p>The more distinctive details from the source work that are used, and the fewer original details that are added, the better the case that the new work is derivative. There is no clear bright line on what is a derivative work. It is a judgement matter, and will be decided by a court if things get that far.</p>
<p>Also, in some cases character names are trademarked. Using a trademarked name in such a way that a reader might believe the new work was endorsed or authorized by the makers of the source work may be trademark infringement. &quot;Gelatinous Cube&quot; is probably not trademarked (although I have not checked) but I am reasonably sure that &quot;Gandalf&quot; is. A disclaimer, noting the trademark owner and saying that the is no affiliation or endorsement can help avoid trademark liability, but it does nothing for copyright issues.</p>
<p>If a trademarked name is used to advertise or market the new work, that makes the case for infringement stronger.</p>
<p>Note that trademarks are matters of national law. A term trademarked in one country may not be in another. Copyright on the other hand, applies world wide, although the details vary by country.</p>
<p>Using the basic idea of the Gelatinous Cube, but changing the details and the name, is not likely to be a trademark or copyright infringement, unless so may other details are imitated that the work as a whole is considered derivative.</p>

law-in-fiction