This quest starts immediately after turning in the sword to Sledrig in the quest Echoes.
Sledrig will mount a Resonance Crystal into the sword, and reveal its true name - "Venzahkrii" - before returning it to the player.
This sword gains a charge whenever the player shouts while it is equipped. The next time they swing the sword, a horizontal beam of energy will fire out in the direction the player was facing - damaging anyone it comes into contact with.
Sledrig will then inform the player that they've been working on tracking down the location of the dragon.
The player will be tasked with following up on some of the leads with Tyriana, Olvus, and Valerine. Each of them will have a task for the player; they are free to pursue any or all of the leads.
Olvus will send the player to speak to a fisherwoman named Branir who is outside of Dawnstar near the water.
In order to complete Olvus's task, the player will need to know how to play an instrument. During dialogue with Branir, she'll suggest that if someone could play some music, she might be able to remember the old song that her grandfather sung to her which mentioned a dragon.
If the player knows how to play an instrument, they will have a dialogue option to play for Branir, who will then sing along and reveal her clue.
Tyriana will send the player to speak to Terit who is stuck unable to enter the inner chamber of the Temple of Dibella due to their rules against males entering.
Terit will ask the player to sneak into the inner sanctum of the temple and steal "The Chalice of Opus" from inside without getting caught. Doing so will cause Terit to share his information.
Alternatively, the player has potential dialogue options available:
Valerine will send the player to speak to Hemid, who is currently visiting the College of Winterhold.
If the player has learned Emissary skills from Valerine, they will have a (Diplomacy) option in dialogue, which will allow them to use the Emissary system to help Hemid recall his information.
Hemid is most susceptible to Whimsical options; using those will lead him to recalling a speech he gave on a dragon that may have been Volgaafsonaan.
Once the player returns to Sledrig, if they have completed any of the professors' tasks, they can tell him about the results which will lead to him surmising a location.
If the player has failed one or more of the tasks, Sledrig will offer an alternative and hand the player a note. This note will reveal a random dungeon location where the player can find a scroll to help them locate Volgaafsonaan. After retrieving this item from the boss chest in that dungeon, returning to Sledrig will allow things to proceed.
After Sledrig has a lead, the quest will complete, and Sledrig will tell the player to prepare while he investigates the potential location.
The next quest will start immediately.