Cypher

Cypher is Brotherhood of Steel's spy in the raider camp of Freeport in 2197.

Background
He isn't a member of the Brotherhood, but is sponsored by them in exchange for information. Cypher is a greasy, shifty-eye looking character who fits in well in any bandit or Raider camp. He has a knack for blending into the crowd as long as they are bloodthirsty marauders. Taking the average wastelander into account, Cypher is practically invisible.

Appearances
Cypher appears only in Fallout Tactics.

Behind the scenes
It seems likely Cypher is a reference to his namesake in the first Matrix movie - (Lu-)Cypher is a spy and a traitor working for the Agents to bring down the Matrix hackers, and almost succeeds.