Wraith

Accept the hunt bill from the Notice Board.

Find Milha in Rabanastre: Lowtown, east of the Traveling Merchant in North Sprawl.

Head to the Garamsythe Waterway, specifically the Overflow Cloaca accessible via Storehouse 5.

As you approach the middle of the room, the Wraith will appear.

Warning: The Wraith can inflict Doom, which will kill a character when its timer runs out. It will also attempt to re-cast Doom on revived characters.

If possible, inflict Silence on the Wraith immediately to block most of its magic. This can be done with Black Magick (if you have a Black Mage or Red Battlemage), the Mage Masher dagger (requires a Shikari), or Silent Shot from the Marksman’s Delight Bazaar bundle (costs 550 Gil and can be used by any job, including Balthier). If you cannot inflict Silence, consider postponing the hunt.

The Wraith also uses Sleep Touch and Poison Touch; be prepared with Antidotes.

When the Wraith is below 20% health, it will begin using Blizzard, Blind, and Dark magicks. Dark is particularly troublesome as it is an area-of-effect spell.

If Silence is successfully inflicted, you will only need to worry about the Wraith's physical attacks and Doom.

You can steal a Glass Jewel, Dark Magicite, or Hi-Potion from the Wraith.

After defeating the Wraith, return to Milha in Lowtown to claim your reward.