So, there's a Floppy Skull Fungus Hat, which I have. It's cute. There is also a Skull Fungus item, but ...

There don't seem to be any in existence. At all. Anywhere.

What's the story behind this skull fungus? :c

It's an attack in the Battle Coliseum generated by the Batwing Blade . It does not exist as an actual item you can own.

Awwww. Pretty cute though.

Oh well, thank you for figuring it out! ❤️