Anyone can audition for these Troopers as there is more than one Stormtroopers of course. But starting the second film, the Shadow Order Troopers (An original trooper character from me) will replace the Stormtroopers. If you audition for the Stormtrooper and deliver the audition lines sounding like a Stormtrooper, I will give you the script and where your line will be in.