The main protagonist in "Rainbow Six: Vegas", Keller is seen in the opening level of the game. Keller demonstrates a formidable sense of close-quarters combat (CQB), with realistic analyses of certain hostage situations and how to eliminate the opposition in an effective and concise manner. He is later seen after Bishop's showdown with Nowak at the end of the game. Logan is seen quoting Bishop's teachings at the last level, implying his respect towards Bishop.