The Volkodavs, or "Wolf Crushers," are an infamous Dacian cavalry unit who serve, as required by The Treaty of Kal-Tordek, as light horse patrolling the Infinite Steppe. The Volkodavs wear long, full-body suits of thick quilted armor, with long coats of chainmail set between two of the layers of cloth, and distinctive "Dogs' Head" helmets (a sort of zischagge with a hounskull-like visor.) They carry crannequin-spanned crossbows, swords of their choosing (Sabers, Koncertzes, and Karthacki Tulwars are perennial favorites) and what they call a "lance," which is in fact a soliferrum that is thrown instead of thrusted with. Since the Dacian people have never really known feudalism, the Volkodav is the closest thing they have to the concept of a "knight." The Volkodavs are known among the Dacians as folk-heroes and sex-symbols. Among everyone else, they are known as savage maniacs, barely a step above the bandits they hunt.
The Volkodavs themselves were not named as such at their formation. Drawn from the few Dacians who had experience riding horses (mostly mercenaries who had fought in the Reich or for the Alandi) the group was initially called the Border Guard, and they were sent, along with the Osterbijan group, to try and bring order to the steppe that had become overrun with nomads, bandits, small raiding parties of Marju, and other scum who had served the Marju Orda as mercenaries and informants.
The Border Guard fought these steppe bandits, and suffered many humiliating defeats because of their untested tactics, lack of experience fighting this sort of enemy, and unfamiliarity with the steppe. Eventually however, they started to catch on. The Volkodavs were initially a splinter-group within the Border Guard that distinguished itself by erasing the lines between "Bandit" and "Steppelander." The Volkodavs were vengeful, ruthless, and became known for and because of their willingness to repeatedly throw themselves into unnecessary confrontations, the most experienced of their kind. Eventually they developed the tactics and equipment for which the Volkodavs are known today, and finally pulled a bloodless coup by voting in their leader as Master of the Border-Guard, and changing the organization's name to their own.
The Volkodavs are not better horsemen than the Marju, certainly, but they are definitely capable riders. The Volkodav Faction of the old Border Guard was made up of hill bandits and brigands who were granted amnesty after the Civil War ended because they knew how to ride horses already, and part of the reason they successfully took over the Border Guard and changed its title to match their own was that they were the best riders. Now they oversee training, and their experience has leeched into the rest of the group.
That said, they're still no match for the Marju in a test of pure skill. However, they have other advantages. As someone mentioned, they have forts in a "deep" defensive scheme that makes it very difficult to simply penetrate past the Sich and wreak havoc on the undefended lands behind it. Their men are from a very violent generation and have a lot of experience with swordplay, and their weapons are generally of better quality than what is available to a Marju warrior.
Even so, the Volkodavs fear unified Marju resistance, which is why they work so hard to create division within the local tribes, funding weaklings and harassing stronger groups in anticipation of joining the fight themselves. The Volkodav sensation in Dace itself is rooted in how different they are from the rest of the Dacian military. Where Dacian soldiery has always been known as ragtag, lightly (if at all) armored, and short, the Volkodavs are uniform, well armored and faceless, and ride horses, making them look much taller. The "Bandit" attitude fostered by the men also gave them a romantic charm to the people, reminding them of the mercenary armies of yesteryear, except better looking, better dressed, and heroic rather than feared.