X-Qar was the first Sentinel of Aether. She discovered the planet and led the Luminoth to settle there during their Golden Age. She was succeeded as Sentinel by Q-Cis. Her's is one of the four statues in the Hall of Honored Dead in the Temple Grounds.
- "This is a statue of X-Qar, the first Sentinel of Aether. It was X-Qar who discovered the world of Aether, and led her people to settle on its wondrous surface." —Scan Data (Metroid Prime 2: Echoes)