After Baderon sends you to Miounne in Gridania, she and Lewin ask you to investigate suspicious activity at the Tam-Tara Deepcroft.
Requirements
This quest is available if you have completed the quest Call of the Forest, and have reached level 16.
Starting the Quest
To start the quest, talk to Mother Miounne in the Carline Canopy in Gridania. There will be a cutscene.
Speak with the Quiverman
Leave Gridania via the southeast gate, or choose Blue Badger Gate from the main aetheryte of Gridania.
Make your way south past Bentbranch Meadows, then go southwest between the stone walls to reach a gate to a stone structure beneath a dome. If you watched the cutscene in Limsa Lominsa after completing Sastasha, you may recognize Dolorous Bear and his companions, who are now outside of the gate. You also see Isildaure and Alianne, who are recovering after a narrow escape.
Go through the gate into the domed area and talk to the Gods' Quiver Bow to add The Tam-Tara Deepcroft to the Duty Finder and Duty Support. As before, you can find Duty Finder and Duty Support in Main Menu > Duty. If you wish to use Duty Finder instead of Duty Support, and you have used Duty Finder during your current play session, make sure to click "Clear Selection" to uncheck any duties that you may have selected previously, then select The Tam-Tara Deepcroft and click Join to join the queue. Or you can click the glowing Entrance nearby to select Duty Finder or Duty Support to the Tam-Tara Deepcroft.
Duty Roulette
Now that you have unlocked two dungeons, the Duty Finder will now have a "Duty Roulette: Leveling" option if you select the roulette icon above the list of duties in the Duty Finder window. Leveling roulette will choose a random dungeon from the ones that you have unlocked, and you will get a significant amount of EXP once per day as a reward for using leveling roulette.
The Tam-Tara Deepcroft
Please see the Tam-Tara Deepcroft Guide for a walkthrough.
Report to Miounne
After you complete the Tam-Tara Deepcroft, go back to Gridania and talk to Miounne. There will be a cutscene. This cutscene shows a continuation of the story of Edda and her companions, whom you may have talked to outside of Sastasha earlier.
Next Main Scenario Quest
After you complete the quest, talk to Miounne to accept the next quest: Call of the Desert.