This is Part 3 of the canonical playthrough . It is the third base-game pillar — the Isu / First Civilization thread — and the mandatory prologue to Fate of Atlantis .
How Atlantis actually unlocks
You cannot sail to a map pin called Atlantis on day one.
- Reach Chapter 6 of the family arc and finish United Front on Naxos.
- Play A Family’s Legacy. It sends you to Thera (the volcanic island marked as the Caldera of Fate).
- Redirect the light beam into the sealed door, go inside, and meet Pythagoras — your blood father, not Nikolaos.
- That starts the Between Two Worlds line and the quest The Gates of Atlantis. Pythagoras will not seal the city until you bring four Precursor artifacts.
Those artifacts sit on four mythical “gods” the Greek world has been telling stories about. Each is a full quest chain, not a single arena fight. Recommended level is the high 40s to 50. Do the family ending first if you are underleveled; the beasts will wait.
The four artifacts
Sphinx — Boeotia
Quest chain: Lore of the Sphinx → Awaken the Myth.
The statue sits on the southern shore of Lake Kopais. You recover an amulet and return at night. This is a riddle trial, not a spear fight. She asks three questions from a larger pool (time, rivers, death, the moon, memory, and similar). Answer, then pick the matching symbol on the nearby pillar. The wrong symbol kills you on the spot. The artifact drops when you walk out alive.
Cyclops (Brontes) — Forgotten Isle, via Kythera
Quest chain: A God Among Men → Left to Dye → Stairway to Olympos (starts on Kythera, the island at the bottom of the map).
The fight is not on Kythera itself. The chain ferries you to the Forgotten Isle. Brontes is a smash fight: watch the stomp, climb when you must, do not stand in front of the club. This is the artifact people miss because they look for a Cyclops cave on Andros and never start the Kythera lead.
Minotaur — Messara (Crete)
Quest chain: Myths and Minotaurs → Of Minotaurs and Men → He Waits (sometimes grouped under A Place of Twists and Turns).
The Labyrinth of Lost Souls under Knossos is the whole point. Bring fire, mark your route, and treat the Minotaur as a small-room boss. This chain also sits near Cultist Swordfish, so you can feed Part 3 on the same sail.
Medusa — Lesbos
Quest chain: Romancing the Stone Garden → Love’s Long Shadow → Hard to Artemis → Heavy is the Spear → Keys to Happiness? → Writhing Dead.
Medusa waits in the Petrified Temple on Lesbos. Petrification beams punish greedy melee. Use cover, range, and the environment. Kodros, the Delian League’s high-level adept, lives on this island as well — another double-dip with the Cult board.
Seal the gates
Back on Thera, place all four artifacts on their pillars. The chamber lights a Precursor map. Pythagoras’s role in keeping Atlantis shut becomes explicit. You seal the city. That is the base-game Isu ending (Atlantis Ending in the old guides).
Modern-day Layla continues in the same space. For the Eagle Bearer in 422 BCE, the next written chapter is not more beast hunting. It is Legacy of the First Blade if you have not played it, then Fate of Atlantis, which uses the Staff you are about to inherit.
If you jump into Fate of Atlantis with the gates still open, you are skipping the scene that explains why the Staff needs a Keeper.
Watch
The hero video is the Gates of Atlantis compilation (all four bosses and the seal). The Minotaur chain is also recorded as A-maze-ing Victory .