daosiying said: I question why have a trumpet if you're wearing a mask/helmet that covers your face.
Well, it's a bit like asking why Spiderman's mask covers his eyes if he wants to see. I guess that just like the eyes on Spiderman's mask are transparent from the inside, the mouth part of Ibuki's mask is made of a special ultra-light textile that covers his mouth from view but does not significantly restrict air flow.