Thanks to Rinual's Mod Menu I discovered that Iris has a hidden talent. She can incapacitate MTs!
Iris doesn't get the chance to fight the imperials when the bros raid the fortress in the main story, but by using the mod and adding her as a guest you can let her join the fray. Use her Eclipse technique and you can watch her practically ripping the heads off MTs. Pretty badass!
Game footage copyright Square Enix Co Ltd.