The Dawnguard Add-on for The Elder Scrolls V: Skyrim has 10 achievements.
Learn all three words of Soul Tear
Use the special power of Auriel's Bow
Complete "Lost to the Ages"
Complete "Kindred Judgment"
Complete "Beyond Death"
Complete "Awakening"
Change your face
Acquire 11 werewolf perks
Acquire 11 vampire perks
Defeat a Legendary Dragon