Atlantis

Atlantis was an ancient and advanced Isu city, the remains of which were situated at the bottom of the Aegean Sea, beneath the island of Thera, Greece. Prior to its final destruction, the city was ruled by Poseidon, and it was one of the Sister Realms, which it formed together with the Underworld and Elysium. They appeared to defer to the authority of Mount Olympos.
==Description==
The Greek philosopher Pythagoras compared Atlantis' function to that of a library, containing all of the knowledge of the Isu; including their physiology, scientific advancements, historical knowledge, culture, and beliefs.
==History==
===Isu Era===
During the Isu Era, Atlantis was created to be an indestructible repository of Isu knowledge where both members of the First Civilization and humanity could co-exist.Assassin's Creed: The Essential Guide The city was originally ruled by the Isu Atlas but he was supplanted by his power-hungry father, the Trident King Poseidon, who gave Atlas and his nine brothers the subordinate position of Archon to manage the city's affairs.Assassin's Creed: Odyssey – The Fate of Atlantis: Judgment of Atlantis – Layla Hassan's personal files: "Bios of the Gods: Atlas"
Poseidon, as the Dikastes Basileus, the Grand Adjudicator, implemented a cycle system for Atlantis wherein the city would be destroyed and reconstituted afresh every seven years if it was judged to be imperfect,Assassin's Creed: Odyssey – The Fate of Atlantis: Judgment of Atlantis – Welcome Home a process which could wipe individuals from existence. Record of the cycles was not kept initially, and at least one was rumored to have not been seen through to completion. According to an Atlantean myth, a matter which led Poseidon's loathed brother Zeus to visit the city and reprimand Poseidon in-person enraged the Trident King so much that he destroyed the very cycle in which the meeting had occurred.Assassin's Creed: Odyssey – The Fate of Atlantis: Judgment of Atlantis – Isu codex: "Various: A Tale of Brothers"
Poseidon eventually outlawed the use of experimentation on the city's human residents and looked to enforce the ban from Atlantis' eleventh recorded cycle. To "lighten the weight of judgment,"Assassin's Creed: Odyssey – The Fate of Atlantis: Judgment of Atlantis – Isu codex: "The Father of Atlantis II" and with Atlas deemed not yet ready for the responsibility of ruling, Poseidon established the role of Dikastes, which was second only to himself and was meant to ensure that matters concerning the city's Isu and human populace were treated impartially.Assassin's Creed: Odyssey – The Fate of Atlantis: Judgment of Atlantis – Isu codex: "Various: Duty of the Dikastes" The Isu Aletheia became one such Dikastes.Assassin's Creed: Odyssey – The Fate of Atlantis: Judgment of Atlantis – The Fate of Atlantis
===Aletheia's simulation===
Around the year 422 BCE, the Spartan misthios Kassandra visited the Gateway to the Lost City, which connected Atlantis to the surface world. There, she discovered her biological father, Pythagoras, along with the Staff of Hermes, which had kept him alive for over fifty years after his disappearance.Assassin's Creed: Odyssey – A Family's Legacy Together, they used the Atlantis artifacts to seal the entrance to the city.Assassin's Creed: Odyssey – The Gates of Atlantis
To help her master the Staff, Kassandra later visited a simulated version of the city, a composite of Isu memories including those of former Dikastes Aletheia and perceived by Kassandra with Ancient Greek imagery culturally familiar to her.Assassin's Creed: Valhalla – 21st century conversations After completing her trials, Kassandra and Poseidon sank the city by using the Staff in conjunction with the Prize of Cerberos and the Prize of the Hekatonchires.
==Behind the scenes==
The exact nature of Atlantis' cycle system is unclear. More recent entries in the Assassin's Creed franchise have typically distanced their world-building from the idea that the Isu were capable of time travel or reviving the dead,Assassin's Creed: Project Legacy – Holidays: Chapter 1 – Ghosts of Christmas PastAssassin's Creed III – 21st century conversationsAssassin's Creed: Rogue – Numbskull's personal files: The Phoenix Project: "The Ankh"Assassin's Creed: Syndicate – Database: Reconstructed Data 011Assassin's Creed: Conspiracies possibilities hinted at in earlier works.Assassin's Creed – Email, subject header "Analysis"Assassin's Creed – The Ankh of Isis Trilogy However, Assassin's Creed: Valhalla has indicated that they had the technology to simulate and inhabit alternate futuresAssassin's Creed: Valhalla – Layla Hassan's personal files: "The Yggdrasil Chamber" rather than just predict.
==Appearances==
*Assassin's Creed IV: Black Flag 
*Assassin's Creed: Odyssey 
**The Fate of Atlantis: Judgment of Atlantis 
*Assassin's Creed: The Essential Guide 
*Assassin's Creed: Valhalla 
==References==
es:Atlántida
Category:Isu territories
Category:Isu locations
Category:Greek mythology
fr:Atlantide