One of the missions in Assassin's Creed Odyssey: Judgment of Atlantis is called Wisdom of the Ancients. This is a special knowledge that will allow you to move through the mystical land. Read this page to learn how to gain this wisdom and what is the goal of this mission.
What is the goal of this mission?
To complete this mission you have to get three levels of Isu knowledge. Thanks to this, you will be able to open any gate in Atlantis. This is one of the most important requirements for you to continue the story.
How to gain knowledge of the Isu?
Knowledge of Isu can be obtained from the Keeper's Insights. This is one of the easiest options because it can be done during the story missions.
Remember that there are only three locations with Keeper's Insight - Insight of the Titan, Insight of War and Insight of Blessings.
The second way is to scan the Isu Data Cache - these are the small boxes shown in the screenshot above.
During your exploration of the world, you can come across Isu codex - they aren't marked on the map in any way.