Defender Sibley

Defender Sibley is a member of the Brotherhood of Steel Outcasts located at the Outcast Outpost in Bailey's Crossroads in the year 2277.

Background
Sibley comes off harsh in your first encounter and stays that way throughout your stay with the Outcasts. He is the one in charge of the mutiny at the end of the simulation.

Quests

 * Aiding the Outcasts: He takes the player to Olin and the VR pod when he's told to do so.

Effects of player actions

 * Once the player completes the Anchorage Reclamation simulation and opens the locked door to the armory, Sibley will attempt a coup d'état with his men against Protector McGraw, feeling that the player doesn't deserve any of the technology within the Armory.

Other interactions

 * If you enter the Outcast Outpost wearing Outcast power armor, found on many of the Outcast reinforcements outside of the base who are killed, he will mistake you for one of them, and will take you to McGraw thinking this. On the way, many of the other Outcasts will assume your unit was one that recently left Lyons and the Brotherhood.
 * If your player is a female, and you have the Black Widow perk, a unique dialogue option will appear when you enter the base and speak to Sibley.

Appearances
Defender Sibley only appears in the Fallout 3 add-on Operation: Anchorage.

Behind the scenes
Outcast members Sibley, Olin, McGraw and Morrill, all of whom appear in the Operation: Anchorage add-on for Fallout 3, appear to be named after buildings on the campus of Cornell University, including Sibley Hall, Olin Hall, Olin Library, McGraw Hall, McGraw Tower and Morrill Hall.

Bugs

 * If you leave the Outcasts Outpost after Sibley tells you to follow him, he will chase you across the wasteland. You can use him as a follower but he only moves at a walking pace. If you initiate dialogue he will talk as if you are in the Outpost.
 * Sometimes, even if you have the Black Widow perk, the single dialogue option with Sibley (when you enter the base) is that of following him to Protector McGraw. After taking the Neural Suit, Sibley will say only "Go bother someone else, local".

Sibley