This page explains how to complete the level 90 post-Endwalker quest "Alzadaal's Legacy".
This quest is available if you have completed the quest Friends for the Road.
Starting the Quest
Talk to Y'shtola in Thavnair to begin the quest. There will be a cutscene.
Use the Duty Finder or Duty Support to enter Alzadaal's Legacy. Please see the Alzadaal's Legacy (Duty) Guide for a walkthrough.
After you complete the duty in Alzadaal's Legacy and exit the area, there will be a cutscene.
Speak with G'raha Tia
Talk to G'raha Tia to complete the quest.
Next Main Scenario Quest
After you complete the quest, talk to Y'shtola to accept the next quest: A Brother's Grief. There will be a cutscene.