If you're a professional, yeah. They're for playing Duel Monsters-- it's a popular game back home. In Action Duels, normal holograms of your cards become real!

[Yuya hops off of his seat on the balance beam, spreading his arms out wide like he's addressing an audience.]

Duelists locked in battle! Kicking the earth and dancing in the air alongside their monsters! They storm through this field-! [He's pretty enthusiastic about the chant, be he stops short-- laughing to himself as he rubs the back of his head.]

It's basically like a sport back home.