Cephla Lake Cave is in the Eldin Canyon area, north of Foothill Stable.
Cave Location
Cephla Lake Cave is located at 2594, 1328, 0152, which is north of Foothill Stable and Kisinona Shrine.
Cave Features
Before you go into the cave, talk to Domidak and Prissen outside of the cave to start the quest Misko's Cave of Chests.
In the entrance tunnel, look to the left to see a small tunnel. Go through and you will find this cave's Bubbulfrog. Then go back through the tunnel and keep going left to enter the main cave.
In the cave, you will find some ore deposits, fireproof lizards, and brightbloom seeds. As Domidak and Prissen explain (see the quest above), all but one of the chests in the cave contain a single green rupee. See Misko's Cave of Chests to find out how to find the correct chest. Or, just open the chest at , and you will obtain . Then check on the bottle to start Misko's Treasure: The Fierce Deity.
After you obtain the full Fierce Deity set as explained on the quest page above, return to this cave and wear the full set. The stone door will open, revealing another of Misko's treasures. Open the chest to get the Fierce Deity Sword. Now that you have acquired this sword, you can purchase it again from Bargainer statues in the Depths.