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