A system termed “named non-artifact properties”. They are unique properties that never generate on more than one item per game, and confer some artifact-like qualities, but are not tied to a specific type of object, and can generate on multiple types of base item. This type of property cannot be wished for, even if properties can otherwise be wished for.

A couple examples:

• Any random ring could generate with a property that causes it to be named “Serpent’s Bite” and gives you a minor poison attack when hitting something with bare hands and the ring equipped.
• A few different types of fruit could generate with a property that causes it to be named “from Eris’s garden” and cause aggravate monster when carried.