Thundra Plateau Cave is southwest of Lindor's Brow Skyview Tower.
Cave Location
Thundra Plateau Cave is located at -2268, 0912, 0110, which is southwest of Lindor's Brow Skyview Tower. To open it, complete the quest Misko's Treasure of Awakening III.
Cave Features
In the cave, you will find one of Misko's treasures: the Mask of Awakening.
Look at the ceiling and you will see some boulders above a hole. Destroy the boulders or just use Ascend there to find this cave's Bubbulfrog.