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