When a story/game/etc. has a character named Zagreus with the title “Prince of the Underworld”, and Melinoë with the title “Princess of the Underworld”, is this story a derivative of the Hades I & II games? Note that both Zagreus and Melinoë aren’t original creations of these games. They are from mythology & folklore, but they barely appear in ancient documents (Zagreus is basically just a name in ancient myths, and Melinoe only appears in a few Orphic Hymns)
With this particular example, Hades is a derivative of actual Greek myth. If another game happened to have the same characters and themes, I would not assume they ripped off Hades unless it also had similar gameplay. God of War has some of the same mythical characters from Greek and Norse myth as TitanQuest and the Marvel comics; niether is derivative of anything but the ancient myths they were inspired by.
You can use the art for the Magic: the Gathering set Lord of the Rings as an example of what you can and can’t do. Hasbro got the rights for the books, not the movies in making the set. That meant all the art for the various characters couldn’t reference or even look like the movie characters.
Because they had to rely on the books only and couldn’t rely on the movies at all, the art on the Magic cards made Aragorn black to be more in line with the books.