They say a true warrior needs no weapon but his own mind, but having a sweet sword never hurts when you're traveling through Ooo. You never know when you might bump into The Lich, casting some kind of diabolical spell to destroy all life, or when Ice King will want to throw down. Heck, you might even need to turn it into a 4 dimensional sword, so you can cut a black hole you accidentally created to impress Princess Bubblegum. Most likely though, what you'll probably end up just swinging it around your living room while shouting, "mathematical!" (That's what we do with it).