From my turn-in post:
I spent the month researching the Muggle phenomenon known as a goomba, which is a fanged creature in the Muggle “video game” that follows the adventures of a man named Mario, one of those pumbles Muggles hire to fix their pipes. (He seems always to be rescuing a princess, though this distressing damsel always seems to be in another castle. How frustrating.) I surmise that the Muggle responsible for the creation of such a beastly creature as a goomba had a chance encounter with some variety of Horklump. Happily for the Muggle in question, the Horklump is rated a mere X (“boring”) by the Ministry’s Department for the Regulation and Control of Magical Creatures, so he was in no real danger.

This particular hat was fashioned after the likeness of the goomba, though why anyone would want to wear a biting mushroom on their head is beyond me. Initially, there was much gnashing of teeth from the goomba effigy, though thankfully I was able to work out a spell so that the goomba is rendered innocuous and good for the wearing. ::shudder::

A Muggle acquaintance of mine requested the creation of such a hat. He also requested a Chain Chomp, though my specimen seems to have broken its chain and bounded off. I was attempting to finish that spellwork and turn them in as a dangerous duo, but I must first search the corridors to find it.

Construction notes:
According to HoJo, Paddy “gets cold easily”, so the hat is double layered.