Fetch the Avian Artifact is a quest given by Esther after turning in Find Clues to Locate the Avian Artifact, having scanned enough clues to unlock the location of the artifact.
Players can travel to the Great Sovereign Temple from the missions tab in their ship computer. They can use this interface to return to the mission at any time in the future to replay it.
The artifact is at the end of an ancient Avian temple, the Great Sovereign Temple. There are a number of hostile constructs throughout, and players must also defeat a boss at the end of the mission; the Kluex Avatar. They'll also encounter a friendly Avian who will help guide them through the mission named Tonauac.
After defeating the Kluex Avatar the path to the artifact is unlocked and players can recover it and return to Esther. Tonauac will also join her at the Ark.
This quest is a prerequisite for Find Clues to Locate the Apex Artifact, which unlocks the Apex mission.