Sonder has helped the Hawthorne Guild during the The March of the Dawn Titan. He initially portrayed himself as a member of the Harpers until he trusted them enough to share his allegiance to the Keepers of the Celestian Order.
In late 1494 DR, he was ''kidnapped'' by a group formed of Rickard, Kingswell Cooper, Ivinka, Sorrel'Svidal Farri and Rex Underhand. He was ''rescued'' by Landis. Since then, whenever Sonder notices one of these aforementioned guild members, he hides or walks/teleports away as fast as possible. He also never walks around without his spellbook, component pouch or spellcasting focus anymore.
In 1495, Sonder went to help a member of the Order of the Dawn named Christopher Wallace. They were meant to look for an abandoned cell of the cult of the Veil, but found themselves within the grasp of Cultists of Atropus. They were later rescued by Ophelia D'Vespere, Rickard, Loric Aloro and Landis.