The Sarmatians were the first mostly-mounted force the Romans came up against, and they represented techniques that the Romans didn't really have an answer for -- charging mounted warfare.

These figures are almost all Freikorps, I believe.  They can really defend themselves -- I armed them all with pins to replace whatever they had before.  I've stabbed myself with these figures many many times.

The greenish blue color of much of their armor is attested in historical documents -- it is scale armor made from horse hoofs.  Other reddish or brown armor is cuir bolli (leather stiffened in wax); only rare Sarmatians would have any metal armor beyond perhaps their helmet.  They did not use shields; their preferred weapon was known (by the Romans and Greeks) as a kontos -- which is a word for a boat oar.  A two-handed spear, really long.  Some of them fought with bows (as well or instead).  Their horses were often armored as well, but their very aggressive tactics cause them to be classed as Knights rather than Cataphracts.

Sarmatian Knights Charging