Hallu! So I recently posted up post #8022854 , which has been bringing me all sorts of headaches ahaha
To the point of this post, the artist, shawn_ger_lin, appears to be drawing their own artistic world which they dubbed "Dice Clan." The theme of which appears to be six-armed women that use or allude to six-sided dice. Pretty much all of their art in their tag is Dice Clan. Now, were it just one or two I don't see this as too big of a deal, but they also seem quite busy with commissions and you can find quite a lot of art of this concept.
So that brings me to the specificity of creating a new copyright when it comes to something that an artist creates. monster_girl_encyclopedia comes to mind, as that wasn't based on a specific copyright but a specific artist's world and concept.
When does an artist's own artistic world get large enough or pervasive enough that it deserves it's own copyright?