The Traitor's Keep Add-on for Fable III has 10 achievements worth 250 gamerscore.
Survive an assassination attempt.
Defeat Professor Faraday.
Defeat Witchcraft Mary.
Defeat General Turner.
Decide the future of the Keep.
Help Huxley end his Loneliness Mode.
Find all of Professor Faraday's diaries.
Find all of Witchcraft Mary's diaries.
Find all of General Turner's diaries.
Open all Demon Doors.