"-mystical fascination and reverence for the Endless. Previously friends with the Sophons, they are a blend of educated scientists and tattooed mystics, and have dedicated themselves to finding the Endless homeworld of Tor." 

 -Descrption of Pilgrims on Endlesswiki


So If and when a faction with piligrims in its population find the Planet Tor, that should triger a quest.

If any one has an idea for such a quest please mention it in the comments.