Main Quest (Shadowkey)

Azra's Crossing Quests
These quests must be completed in the order they appear.
 * Find the Temple
 * Herb Quest
 * Rescue Prisoners
 * Clear Earthtear Caverns
 * Collect Five Star Teeth

Star Teeth
These quests don't have to be completed in order, but at least five Star Teeth must be collected to progress in the story line.

Witch Tree Tooth

 * Witch Tree 1
 * Witch Tree 2
 * Broken Wing Cameo
 * Witch Tree 3

Proliss Caith's Tooth

 * Either:
 * Proliss Caith Subterfuge
 * Proliss Lakvan Evidence
 * Or:
 * Tanyin Goblin Raid
 * Tanyin Lakvan Evidence
 * Tanyin Mages' Guild
 * Tanyin Prisoner Free

Azra Nightwielder's Tooth

 * Either:
 * Find Azra Nightwielder
 * Or:
 * Mage's Identity

Additionally, the three others are found in Lakvan's Stronghold, Broken Wing, and Glacier Crawl which can only be found by free-roaming or finding them while on other quests.

Crypt of Hearts
The final quest strangely does not have a formal entry into the journal. The player must travel to the Crypt of Hearts and insert the Shadowkeys and the Star Teeth into their proper position, and only then can the Umbra'Keth be defeated.