An acton was a special member of the Troyian nobility, similar to a knight.
Actone were expected to obey the law at all times and put a stop to any criminal activity they found, essentially operating as an impromptu police force. They could also take up the causes of wronged victims, who could petition them for aid. The Troyius Tribunal prosecuted those who sought to hire an acton under false pretenses or improper promises.
However, in practice, actone paid more attention to their estates than their duties. Tourist guides about Troyius spoke of them as "knights-errant", but visitors expecting armored mounted warriors would be disappointed. (FASA RPG module: The Orions: Book of Common Knowledge)