It's a fossil that generates in soul sand valleys. While it acts like a feature (like a tree) with generation, it's technically a structure. See https://minecraft.fandom.com/wiki/Nether_Fossil.
I appreciate you sticking to the wiki's definition of structures.
That said, I can't believe dungeons and desert wells aren't considered structures. I also didn't know those would generate even with "Generate Structures" unchecked on world creation. Lame! Not your fault though. Great quiz!
That said, I can't believe dungeons and desert wells aren't considered structures. I also didn't know those would generate even with "Generate Structures" unchecked on world creation. Lame! Not your fault though. Great quiz!