When visiting the Hall of Dread to find information hidden by Patton, Seth heard voices whispering in the Dungeon, and noted he hears them. The voices shut up, and one started to persuade Seth into opening the cell doors, saying he would serve him for a thousand years. Seth told them he has to think about it, and leaveed the hall, with the Wraith saying he would wait.
Later, at Wyrmroost, at the Blackwell, Seth hears voices in it, asking him to open the prison, saying they would obey his every command. Later, when Agad finds Seth, he hints that the creatures in the Dungeon are very powerful Undead creatures, possibly Wraiths, and that the Blackwell is possibly the most dangerous place in the whole Sanctuary.
After the fall of Fablehaven, Patton told Seth to start hiring Wraiths or other Dark Creatures at his service to guard certain places at Fablehaven, such as the House, the Old Manor and the Stables. Seth hired the Wraith from his last encounter, but almost falls into a trap set by it and its two brothers.
After the Centaurs tried to take the Old Manor and the House, the Wraiths beat them back and possibly kill some, as Seth promised them every creature that comes near the house as a reward for their services. This resulted into the Centaurs proclaiming war on Seth. Seth also gets an idea to built a large army out of Wraiths, Liches and other Undead beings, and asks the tallest of the Wraiths what chance would he have against the Demon King, to which the Wraith simply replies "None".
Later, Seth promised three things to the Singing Sisters, Vasilis, the sword of light and darkness, a Wraith to do their bidding, and one thing they wish. It is also revealed Sphinx has a company of Wraiths with which he hunts down Warren. The same Wraiths saved Warren from a Manticore.
The Sphinx told Seth that many of the inhabitants of the Blackwell are Wraiths , who Seth later released. Later Seth asked a Wraith to take him to Ezabar for him to talk to Bracken , the Wraith complied.
When Seth entered the Crypt where the Phantom Dezia lived, six Wraiths attempted to attack Seth , but Seth talked them out of doing it when he granted them freedom if the best one lead him to Dezia , which was a Wraith named Midnight .