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 "Kindred Judgment"
Complete "Lost to the Ages"
Use the special power of Auriel's Bow
Learn all three words of Soul Tear
Complete "Beyond Death"
Complete "Awakening"
Change your face