Order received - it'll be getting packed up over the weekend
I always like being asked questions - it helps me to get ideas actually written up that otherwise tend to stay in my head...
The Casanii territories are a vast swathe of land and there are a lot of different tribes, some very nomadic (following the great herds that migrate across their lands) and others that live in more static villages. There are fishing communities (sea and river) and some towns built around the locations of periodic gatherings where the nomadic communities gather to swap stories and goods (and often there are marriages as young sempa are tempted away by kopa from other exotic tribes).
The nomadic tribes carry tents strapped to their beasts. (Native Americans or African tribes are good for inspiration)
I think of the casanii as having darker skin. (I wasn't going to go that route initially, but it makes sense in the warmer climates) As with other races of fubarnii they do vary in their appearance more than humans do, so there is room to be imaginative.
Most casanii are well behind the fubarnii in terms of many forms of manufacturing (although there are many artisans whose wares are valued throughout anyaral). However, there are strong trade routes between the Casanii and the rest of the Empire (Loranti is a good example) so they have access to metal weapons. They can do some metalwork, but they don't have the machines and the infrastructure of the Empire's engineers.
I think of their armour plates and shields as being crafted from fibrous materials (grass, furs etc) coated in a hard resin that they extract from various species of garkrid. This makes it tough and light (and is a similar technique to that used by the Empire and Delgon for their armour). The armour is usually painted in bright, vibrant colours. There are tribes who have alternative approaches to manufacturing armour, such as boiled leather, but I would not expect to see large amounts of metal as it is too expensive and heavy for the Casanii.
Weapons vary even more. Some are made from special resins, while some are carved obsidian or bones. Some prosperous tribes have traded with the empire for metal weaponry (and others have taken weaponry in a less harmonious fashion), so metal spear heads would not be out of place.
I hope that helps a bit!
As with Empire tribes, you are welcome to create your own tribes and histories! If I like them I will of course borrow (steal) the ideas and weave them into the background so they add to the richness of the world. If I don't like them, then I'll just think of them as myths or legends that the fubarnii or casanii themselves tell but that aren't directly part of the world. Certainly feel free to ask questions though - I'll always try to answer and there are others on the forums with great imaginations who may chip in as well