Cavalier
"While many warriors strive to perfect their art, spending all of their time honing their skill at martial arms, others spend as much effort dedicating themselves to a cause. These warriors, known as cavaliers, swear themselves to a purpose, serving it above all else. Cavaliers are skilled at fighting from horseback, and are often found charging across a battlefield, with the symbol of their order trailing on a long, fluttering banner. The cavalier’s true power comes from the conviction of his ideals, the oaths that he swears, and the challenges he makes."
-- Pathfinder Cavalier
In Palimpsest, the House of Ratrider were traditionally Cavaliers, riding trained rats in the Palimpsest cavalry. Since the rise to dominance of the human noble houses, the cavalry has mostly been disbanded, in favour of Elemental and Automata armies.