If the creature was focused on Nida, Ignis didn't hesitate to jump on it. But when it focused on other people, if he could clear the innocent civilians that was priority. And whenever he could, the advisor focused the creature on himself so that Nida could clear the innocent bystanders.

"This reminds me of Altissia." he declared, working his Fire daggers at the damn thing. That was where he, Gladio and Prompto had to clear out the citizens there for for Lady Camelia Claustra per her pact with Noct, in order to make way for Lady Lunafreya and the subsequent summoning of Leviathan.