UPDATE: Here I am thinking the “four elements” were universal. I was just schooled on the traditional Chinese five elements of fire, water, earth, wood, and metal, which would be a more obvious choice for Daiyu to reference! Had I known I would have had to scrap the joke (with a touch of seriousness… I mean, fire breathing ducks=Certain DOOM) so I’ll just pretend Daiyu was schooled someplace where they were all about the fire, air, water and earth. You should too!
Either you get this one or you don't.