- "The Sindu fly like surgeons operate."
- — Emperor Calus
The Sindû, or Sindu, are an alien race that dwell in gas giants in the "spinward marches" and a member species of Emperor Calus's Loyalists. They are exceptional space pilots, with their best being known as Ace-Defiants.
When the exiled Emperor Calus discovered the Sindû, he invited them to join his Loyalists. When the Sindû refused, Calus simply conquered them, destroying their entire star-pilot corps save the Ace-Defiant Jarus, who he chose to join the Shadows. After inducting them into his Loyalists, he repaid them with a new fleet of golden interceptors, and employed their talents in defense of The Leviathan.