It's actually not the first time Zura has said "Zura da", remember back at the end of the Benizakura arc? He slipped up and said something like "Lupin ja nai, Zura da".
Zura really a badass there, i love how Sorachi use flasback on his manga, he just never exploit that and use it on really the rightest moment and ended up enhance the greatness of the story.
And poor Sakamoto tho xD trying to advertise himself but get no recognition..
It's actually not the first time Zura has said "Zura da", remember back at the end of the Benizakura arc? He slipped up and said something like "Lupin ja nai, Zura da".
I love the Granny's quote to Katsura. Katsura janai Zura da. Zura being alone after his parents died and then having Gintoki and the others is heartwarming.