"Dune: Hunting Harkonnens", by Brian Herbert and Kevin J. Anderson, was first released online in 2002 prior to the release of the first Legends of Dune novel, Dune: The Butlerian Jihad; it was later published in the 2005 collection The Road to Dune.
In the short story, Ulf and Katarina Harkonnen and their son Piers (the parents and brother of Xavier Harkonnen) are travelling to Salusa Secundus when they are attacked by thinking machines under the command of General Agamemnon, a cymek. The Harkonnen ship is severely damaged and …