The The Brigmore Witches Add-on for Dishonored has 10 achievements worth 220 gamerscore.
Complete The Brigmore Witches in High Chaos
Purchase at least 8 favors in The Brigmore Witches
Use an enemy lifted with Pull as a shield
Complete The Brigmore Witches in Low Chaos
Complete The Brigmore Witches without alerting anyone
Complete The Brigmore Witches without killing anyone
Restore the Undine to working condition
Break Lizzy Stride out of Coldridge Prison
Deliver (or attempt) the killing blow on Corvo
Survive The Brigmore Witches in low chaos with 10,000 coins