The Improbus was a powerful ship that belonged to Aegrus Claustrum, a bounty hunter and member of Cad Bane's posse. Custom-built by Aegrus himself, the ship was fast, well-armed, and versatile. It could be used for virtually any role, as it could match speed with the fastest of military interceptors, damage capital ships as well as any bomber, and defend itself against heavy fire. Because of the ship's power and flexibility, Cad Bane recruited Aegrus Claustrum for his ship, though he soon regretted it when he learned about Aegrus's naivete.