Locale: Telegrafbukta Beach
When you are at Telegrafbukta Beach use the Submarine
Then use the Helm of the Nautilus (secrets of the Atlantic)
Refill your oxygen at the Ship's Helm (Secrets of the Atltantic)
Use the Rowing Boat
When you're on the Atlantic Ocean use Dakkar's Pendulum.
It will tell you either South West, South East, North West or North East.
For Helena Christensen it was South West and she did the following:
I moved 70 steps South and 70 steps West. Then I used the pendulum again. It said North West. I made 10 steps North and 10 West. Used the pendulum. It said West and I moved 30 steps. I used the pendulum again. I made only 5 steps in each direction only, used the pendulum. At the end I moved only one or two steps back and forth. Then the entry showed up that I had reached my destination - the ancient buoy. Go down the staircase to the Sunken Ruins.
When the pendulum tells you that you have reached your destination, use the ancient buoy/staircase:
Move E-E-N use item and get Ἀτ.
Move S-W-W-W-N-N-NW-N-NW use item and get λαν.
Move SE-S-SE-S-S-S-SW-SW-S-SE-SW use item and get τίς.
Move NE-E-SE-E-N-N-NE-E-NE-N-N-N-N-NE-E use item and get νῆσ.
Move W-SW-NW-W-W-S-SW-S-W-W-SW-S-S use it and get ος.
Then move N-N-NE-E-E-N-NW-N-NE-N-NE and use the gate.
Secrets of the Sunken Monolith
Items for your health
4 xp points
8 xp points if you have completed 1 of the former quests (Secrets of the Deep or the Unholy Diver.)
12 xp points if you have completed both of the former quests.(Secrets of the Deep and the Unholy Diver.)