The Luminoth B-Stl was one of the ten Keybearers sent to collect the Sky Temple Keys. She is called "gallant" by A-Kul. Her mate, J-Stl, was also a Keybearer, and died shortly before she did. B-Stl fell in the Main Reactor of Agon Wastes. When Samus travels to the Dark Oasis of Dark Agon Wastes, she recovers B-Stl's key.
- "Gallant B-Stl. She lies deep in a fortress of dry land." —Metroid Prime 2: Echoes Logbook "B-Stl's Key" (Metroid Prime 2: Echoes)
- "I can go no further. Here in this reactor, I go to join my mate, J-Stl, in final rest. Though I die with honor, a shame falls on my house until the key I seek reaches its destination. May my brothers find my burden, that the way to the Sky Temple will be opened at last." —Metroid Prime 2: Echoes Logbook "B-Stl's Testament" (Metroid Prime 2: Echoes)