If you’re a fan of Adventure Time, you know that the series is chock full of algebraic cosplay inspiration. One particularly cool item from the show is the Ice King’s crown. The crown isn’t just character decoration, and it plays a key role in the plot of some episodes. In honor of the show’s finale — which is airing tomorrow, September 3rd — YouTuber Allen Pan created a replica of the Ice King’s crown that includes some interesting plot-specific functionality.
To outside observers, Pan’s crown simply looks like a well-made — but inert — 3D-printed replica of the one seen in the show. But, when you put it on your head, it comes to life in two different ways. First, just like in the show, it will talk to you, and only you. That’s possible because Pan used a pair of bone conduction transducers instead of normal speakers. Those transducers transmit audio by vibrating your skull, so that you’re the only one who can hear it.
The second feature is a built-in cooler. Before he became the Ice King, Simon Petrikov was a normal fella. But, when he put on the crown, it caused his body temperature to drop and transformed him into the penguin-owning villain we all know and love. To make his crown actually cool the wearer, Pan built in a Peltier thermoelectric cooler. That cooler is on the inside of the crown so it can’t be seen, but it still noticeably chills the wearer’s head. We’re all sad to see Adventure Time go, but Pan’s crown is a totally mathematical way to commemorate the show’s legacy.