[CuriouslyC]

Magic missile by itself is questionable since that language never gets used outside of D&D references, but it is also suitably generic. If you also used Strength, Intelligence, Constitution, Charisma and Wisdom as stats, and had hit dice, and so on, that would be problematic. If you chose new names for everything but the rules were otherwise identical that would be completely safe.

Part of the problem is this is a gray area even in the law, just look at the kerfuffle around the Warhol prince print that is still ongoing.

[mhd]

> If you chose new names for everything but the rules were otherwise identical that would be completely safe

Reminds me of the Judges Guild "Universal System" where they had a lot of weird stats in their books, often with some made-up rules, just to avoid any issues with D&D at the time (late 70s/early 80s, I think).

Event went so far as to have three-digit stats, stating that the first two are the regular ones (to correspond on the D&D 3-18 range) and the last is "how often you can use it without having to roll for a stress test".

If you're going that unusable, you might as well write for your own or a non-litigious system and let the people convert it themselves. It's a lot of homework anyways…

[HelloNurse]

Come on, this kind of "made up rules" is meant to be ignored, not followed. Normal players would have dropped and ignored that extra stat digit, either because they recognized it as a plausible deniability tool whose usefulness is limited to written material or because preferring D&D-like stats is an obvious corrective "house rule".

[mhd]

Yeah, that rule was clearly just there for show. Just like the second digit on levels ("number of professions you've mastered").

There were some rather elaborate rules for constructing armor that didn't really map to D&D's armor class, though. Probably even more of a curve ball.

The hit points – sorry "hits to kill", my mistake – were either what you'd expect from a D&D character with the same (first digit) level or the sum of (the first two digits) of Constitution and Strength.

Don't remember much more than this…

[lcnPylGDnU4H9OF]

I think this is an easy conclusion to reach in this context of a licensing discussion but no player is going to, in the usual context, open a book they've never heard of and think all of the ridiculous rules were put there to avoid copyright issues.

[crote]

I wonder how the ongoing dilution influences this.

For example, World of Warcraft has had the virtually identical Arcane Missiles spell for nearly twenty years now, and Terraria even had the identically-named Magic Missile for over a decade already.

In trademark law lack of enforcement can lead to the trademark becoming genericized, which is why words like Aspirin, Videotape, or Escalator are no longer trademarks but regular everyday words.

If you never enforce your IP rights despite being well aware of violations, and even actively promote use of it by third parties, at what point does it stop being IP and become common culture?