"These ashes are all that remains of a school of illusionists called the Pabulum. According to their expedition logs, they traveled to the Plain of Shale in search of the lost works of the Fosterer, a powerful sorcerer who once ruled an empire where the Plain of Shale now lies.
The naive illusionists were successful, and they stumbled across one of his lost works: a hive of vicious creatures called the Trelons. The remains of the mages were found days later by two Bariaur scouts and were burned over a pyre as a symbol of their folly.
To unlock the power of these ashes, one only needs to stir them with the index finger of the left hand, then sprinkle a pinch of the ashes into the air in a circular pattern. The smell of the remains of these dead mages is said to cause a Trelon to appear to serve the user.
No one knows where the Trelons originated from, but they seem to combine the worst characteristics of demons and insects. They seem to bear an insane hatred for mages, but the reason for this is unknown."
- Summons Trelons
Ashes of the Pabulum can be bought from the following shop:
According to Chris Avellone's short story Chronicle of the Plain of Shale published in Dragon+, Xachariah and a Bariaur called Bentneck were part of the expedition. They were paid handsomely by mages of the Pabulum, a wizard school that hails from the ninth ring of the Outlands, to guide them through the Plain of Shale and hunt the monsters there. They were looking for the Fosterer's lost works, but what only Xachariah realized was that the monsters they encountered there - the Gronks, Grilligs, Sohmiens, and Trelons - were his lost works.
When the plain was still the Bladegrave, the Fosterer bred those creatures there as living weapons. He released the Trelons upon an illusionists' school called the Academy of Weavers in the fifth ring near Curst. After slaughtering all the mages in their sleep, the Trelons vanished, and the Fosterer didn't think much of it... until the night they killed him. As a consequence of the Fosterer's actions, the Bladegrave became the Plain of Shale, and the only thing that ever grew there again was monsters.
The Trelons hate all mages and magic, dooming both the Fosterer and the Pabulum mages. Xachariah related this story to Bentneck and the expedition's chronicler, Kaye, and said the Pabulum had gone beyond the scope of the jobs they hired them for. He convinced them both to leave with him before the Trelons killed the Pabulum mages so they wouldn't have to die with them. They escaped, but their campsite became the Pabulum mages' grave.