Below are the side quests that can be obtained in Tephra Cave!
A Thank You
Obtained: Speak with a Defence Force Solider near Warehouse 2 after reaching the Bionis’ Interior
Objective: Exit Tephra Cave and check the area immediately to the left
Head to Kneecap Hill at the end of Tephra Cave and interact with the dig spot near the exit to complete the quest.
Arachno Silk Fundraising
Obtained: Speak with Defence Force Soldier in Tephra Cave near the Escape Pod Bay
Objective: Collect 3 pieces of Arachno Silk from Worker Arachno in Tephra Cave
The Worker Arachno that drop the Arachno Silk can be found just past the Spring of Grief in the tunnel that leads to Vilia Lake.
Clearing Obstructions
Obtained: Speak with Defence Force Soldier in Tephra Cave near the Escape Pod Bay
Objective: Defeat 2 Devoted Arachno, 4 Resolute Arachno and 3 Zealous Arachno near Vilia Lake in Tephra Cave
The Devoted Arachno are located in the tunnel just past the Spring of Grief. The Resolute Arachno are located further down the tunnel. The Zealous Arachno are located at the very end of the tunnel near the entrance to Vilia Lake.
Collection Quest 1
Obtained: Speak with Defence Force Soldier in Tephra Cave near the Escape Pod Bay
Objective: Collect 2 Kneecap Rocks in Tephra Cave
The Kneecap Rocks can be found on the ground in Tephra Cave.
Collection Quest 2
Obtained: Speak with Defence Force Soldier in Tephra Cave near the Escape Pod Bay
Objective: Collect 2 Bright Figs in Tephra Cave
The Bright Figs can be found on the ground in Tephra Cave.
Material Quest 1
Obtained: Speak with Defence Force Soldier in Tephra Cave near the Escape Pod Bay
Objective: Collect 3 Broken Pincers from Krabbles in Tephra Cave
The Broken Pincers are dropped by the Desert Krabbles in Tephra Cave near the Spring of Grief.
Material Quest 2
Obtained: Speak with Defence Force Soldier in Tephra Cave near the Escape Pod Bay
Objective: Collect 1 lot of Brog Smelling Salts from a Noble Brog in Tephra Cave
The Brog Smelling Salts are dropped by the Noble Brogs in Tephra Cave near the Spring of Grief.
Missing in Action
Obtained: Speak with Defence Force Soldier in Tephra Cave near the Escape Pod Bay
Objective: Speak to the Defence Force soldier near the Cylinder Hangar
Travel to the Rear Entrance then exit Tephra Cave to find the Cylinder Hangar. Speak with the soldier to complete the quest.
The Blood of Bafalgar
Obtained: Speak with Shura at Bafalgar Tomb in Tephra Cave after completing The Book of Bafalgar side quest
Objective: Defeat Dazzling Tolosnia near the Heavenly Window and collect the White Spider Heart
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The Book of Bafalgar
Obtained: Speak with Shura at Bafalgar Tomb in Tephra Cave in Chapter 17
Objective: Find the Starlight Book near Vilia Lake in Tephra Cave
The item is located on the eastern ledge overlooking Vilia Lake. It is reachable by heading south from Bafalgar Tomb. Once the item has been collected, return to Shura to complete the quest.