About Crusader Kings 2

Crusader Kings II: Hymns of Abraham is a DLC that adds 2 songs
Crusader Kings II: Military Orders Unit Pack is a DLC that adds 7 units based on Christian Holy Orders
Crusader Kings II: Norse Unit Pack is a DLC that adds 3 units (Sweden, Denmark, Norway)
Crusader Kings II: Songs of Yuletide is a DLC that adds 2 songs (Deck the Halls and Joy to the World)
Crusader Kings II: Warriors of Faith Unit Pack is a DLC that adds 11 units (Aztecs, Islam, the Norse, and Zoroastrians)