Chaos Marauder Horseman
Chaos Marauder Horseman are Chaos Marauders who are mounted upon Horses. Many a Slaves to Darkness tribe places a great amount of reverence towards the equine creatures - for the hardy beasts are perfect for crossing vast wilderness and running down fleeing prey. Ownership of such beasts is in turn considered to be a status symbol, with the warriors mounted upon them being some of the most feared light cavalry in the Realms - as unlike the mounts ridden by the Chaos Knight, they are bred for endurance and speed rather than strength. 
Horsemen warbands tend to worship the aspects of the Ruinous Powers as bloodthirsty hunter-lords, winged seraphim of inevitable death, and other such preening deities of the perfect kill. The rituals to please these beings commonly revolve around celebrating the moment death is delivered, and often a Horseman's steed joins the rite by trampling a captive under iron-shod hooves. Though Marauder Horsemen are masters of the feigned flight and hit-and-run attack, their devotion to the gods cannot be denied. When battle is joined they will charge into the fray as eagerly as any of their fellow warbands, howling praises and oaths as they ride down non-believers. 
Due to the speed of their mounts, Marauder Horsemen pride themselves on being the first warriors of the Horde to sink their blades into the flesh of the enemy. In addition, they are some of the few Slaves to Darkness that bring missile weaponry to battle, throwing stout javelins into the fray.