After defeating Valaris, Jologz gave more information what exactly took place in the Laboratory. His information stitched all the clues together - the dark and mysterious Ancient Artifact that some explorers past found in the Sea Dungeon located at the West side of Vanadis.
Curious as you normally are, you headed west and found a fishing village on the island itself. After speaking to the local people, you learned the story of the Four Brothers.
Villagers: Story of the Four Brothers
Talk to the villagers in Vanadis to learn about the story of the four brothers (Humility, Integrity, Courage, Wisdom)
Chief: 'The Magnificent Seven
Talk to Chief to learn about the Magnificent Seven.
Chief: 'The Shell King' Slain
Kill the summoned Shell King.
Chief: 'The Evolution Stone' found
You will still have to show an Evolution Stone (can be borrowed from somebody else) to the Chief, then General, then Petra later on the Storyline, but this quest will not be marked (although you can still proceed with the next quests).
Optional: Old Woman - The Missing Son
Talk to the Old Woman to learn about the Missing Son.
Optional: The 'Legendary Necklace of Brokkr' found
Optional: Brokkr - The Legendary Blacksmith
Find Brokkr and talk to him.