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