But once you start breathing into it, the famous Marauder’s Map, as envisioned by the movies based on J.K. Rowling’s novels, begins to appear due to the temperature change. How cool is that?

I solemnly swear to spend all my money on anything and everything Harry Potter-related, and that includes this handmade Marauder's Map mask that changes colors when you breathe into it. Colorado ...

And for Potterheads, this Harry Potter face mask magically reveals the Marauder’s Map when you breathe — and it may just be the coolest mask ever.