[Yuya's aware of Foster's... 'gifts' by now, at least, so although he briefly eyes the bird warily he at least isn't too (outwardly) alarmed.

He jerks his attention back to Gongenzaka with a smile.] You figured it out that quickly? You're getting really good at magic.

[It's not a spell he can think of having seen already, even with Gon's described inspiration. So he came up with it on his own...?] Creation didn't really talk much with words, either. [He puts his hand to his chest.] It was more like it was in here, and that's what I was getting from you! That and pictures.