There are two Paladin class quests that have players go into Shadowfang Keep, one quest for the Horde and the other for the

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Alliance. Both quests are similar, having paladins run through a series of low level dungeons. For the Horde, the quest is called “The Path of the Adapt”, the the one for the Alliance is called “The Test of Righteousness”.
The Path of the Adapt
Horde paladins must enter Shadowfang Keep, Blackfathom Deeps, Ragefire Chasm and Deatholm to complete The Path of the Adapt. In Shadowfang Keep, players are after a crate of Bloodforged Ingots. The crate is located in the stables just off the courtyard that is opened up by Deathstalker Adament.
The Test of Righteousness
For Alliance paladins, the “Test of Righteousness” takes them into the Deadmines, Shadowfang Keep, and Blackfathom Deeps plus they must travel into the heart of an ogre village in Loch Modan. When heading into Shadowfang Keep, Paladins need to retrieve Jordan's Smithing Hammer. Like its Horde counterpart, the item is located in the horse stable.