Grodin Tierce was a Human male who served as a Royal Guard. During the Thrawn campaign, he was cloned by the Grand Admiral as part of a new project to create super-commandos. He died shortly after. His clone was later involved in a campaign to bring down the Alliance, before being killed in the Second War.
As with all Royal Guards, Tierce began his military career as a Stormtrooper. Under the designation TR-889, Tierce ostensibly proved himself an exceptional soldier and was chosen for training as a Royal Guard on Yinchorr.