Sentry consisted of two SCT Scout Craft that served the Galactic Empire.
Shortly preceding the Battle of Endor, they received orders to protect the Vorknkx Project. While positioned at the research hub for the project, Grand Admiral Demetrius Zaarin, who was a traitor, dispatched one of his Nebulon-B2 frigates, named the Z-Borus, with the aim of seizing the CR90 corvette Vorknkx, which served as the project's testing vessel. This vessel possessed the newest Imperial cloaking technology, which Zaarin desperately desired. The Sentry group had the duty of establishing a minefield surrounding the Vorknkx as a defensive tactic when the attack by the traitors happened. The defense of the Vorknkx Project depended on their continued operation, so pilot Maarek Stele was dispatched to defend the ships and facility. Stele was successful in eliminating the majority of Zaarin's combatants, notably the Z-Borus, thus enabling the Sentry group to position their minefield and subsequently evacuate the vicinity. Consequently, the Vorknkx Project remained secure from Zaarin's grasp for a period of time.