Assault on Splinterskull

Seeking Chief Ungurz
You must explore the Tangleroot Gorge adventure area first and find Chief Ungurz, to start this quest chain. After this one-time flag is completed, talking to Emeric Quall in The One-Eared Bugbear Inn will directly send you to Ungurz.

The Deadly Package

 * The Stronghold Key
 * Agent of the Darguul

Doom of the Witch-doctor

 * The Way to Zulkash
 * Zulkash, Herald of Woe

The Last Move

 * The Way to Yarkuch
 * Yarkuch's Last Stand

Collectables
This quest chain is a popular place to farm out collectables. Following is the list of collectables found within the quests.

Bruised Spore Pod, Caravan Logbook, Ceramic Bowl, Charred Soarwood, Cryptic Message, Duskbrood Trumpeter, Flowering Hellscap, Flowering Spore Pod, Fragrant Drowshood, Headsman Beetle, House-Sealed Letter, Intact Spore Pod, Lightning-Split Soarwood, Lodestone, Luminescent Dust, Moonstone, Phoenix Tavern Purchase Order, Research Diary, Romantic Sonnet, Runic Parchment, Silver Flame Hymnal, Singed Soarwood, Skull Fragment, Sour Darkcap, Tome: Codes of the Aurum, Tome: Lost Songs of Cyre