Nomads of the Savanna

The lands of Jamul and Xythia are not only home to the ethnic Xythian peoples, but also generations of invading/migrating Xongu and conquering Telanteans from Zygaria.
Some of these peoples have formed Nomadic tribes for safety in numbers, perhaps not having the resources, time, or inclination to settle down and build a permanent settlement.
Among these groups are several distinct Cultures, featuring ethnic differences, mores and folkways, even languages. There are 40 - 60 of these groups (in total) wandering the Savanna, from Xythia to the Empire, at any given time. They appear in groups of 20-200 (fighting-age men and women), plus an additional 50-60% of the full number in wives, children, camp-followers, craftsmen and tradesmen.
Typically these tribes will meet, all of the Lejontaki for example, every second or third year to exchange news, lore, magic, trade goods and to intermarry their children from one clan into another. the Leaders of the Tribes will take on one or more apprentices for themselves and their levelled followers.
Each tribal people have their own methods of leadership and keeping the peace.
Vohentaki (Goat People) Tribes of goat-herders, who make and sell milk, cheese, meat and horn decorations. Tend to be the most peaceful of the Nomads, rarely getting into fights. Their herds of goats can be very large indeed, numbering thousands of animals. Many of the Vohentaki become Vepitor (Monster Hunters). Vohentaki dress and language are very similar to that of settled peoples.

Lejontaki (Lion People)

Smallest of the Nomad tribes, the lejontaki are known to be mystics and are often treated with suspicion as they are thought to treat with demons for magical powers. The Lejontaki wear the tanned hides of their namesake Plains Lions, as well as silks and other gauzy cloths they trade for, far to the West.

Luo-leymen

Tribes of devolved human “Forgetters” who no longer know the rituals of remembrance for the dead or the basic skills of civilization. Basically “Cavemen” with Stone Age tech and perhaps some found or captured weaponry. These tribes know only to burn their dead, in order to prevent them returning. They have almost nothing in the way of magical resources. A Shaman-type NPC of a self-trained nature might exist, though the chances that they would release a demon or other supernatural entity to devour their tribe is high. It is rumored that Luo-leyman have some Fae blood.

Joygirls

Not really a tribe as much as a profession, the Joygirls consist of small troupes of performers that usually travel with the Wagoneers. The Joygirls provide entertainment for the tribe and for the people of the settlements they visit, such as music, singing, dance and acrobatic routines, performances of plays and dramas, and other public shows. It is a high aspiration to join a troupe of these performers, and they tend to be the most ethnically diverse group of Nomads.

Raincatchers

A specifically Xythian tribe of Nomads who wander the Savanna on an opposite schedule of most tribes. They congregate in the Lowcountry during the rainy season to catch the rainwater in barrels. Thought to have come straight from the sea in the storms of the Monsoon Season, Raincatcher water is a bit salty and is believed to have many healing properties. The barrels the Raincatchers use to hold and store the water are thought to be enchanted, as Raincatcher water is always fresh and delicious.

Unohtaa (Berserkers)

A second tribe of devolved human “Forgetters” who no longer know the rituals of remembrance for the dead or the basic skills of civilization. Just above the description of “Cavemen” with Stone and Bronze Age tech and perhaps some found or captured weaponry. They speak a very guttural version of High Telantean, but can no longer read or write. The Unohtaa are known cannibals, eating any and all humans they encounter. Prized above all, though, is the flesh of the smallest Darklings. Unohtaa have been known to root out entire Darkling cave systems and devouring every one they find.

Vorlutaki (Vorlup people)

Taking their name from the large reptiles they breed and sell to the people of the settlements, the Vorlutaki are the closest to having a sort of permanent settlement, in that they will camp in one place for the time it takes their reptiles to lay and hatch the eggs. The Vorlutaki are excellent smiths, forging many items from bronze and even some iron products. Their steel's physical quality is not up to the standards of that found in Zan's Forge, but the metalworking is.

Wagoneers

The Tanso are an insular people, with a very distinctive look - they have very fair skin, and flame-red hair. Mostly they keep to their boats and barges in a great lake to the north, but some clans venture south for gold and trade. The Wagoneers are the Host-group of the Joygirls, excellent entertainers who put on shows, plays, music and acrobatics. Wagoneers have the most contact with settled peoples of Jamul, and are always welcome, even in the smallest villages (where they usually will perform for food and shelter), as their presence lightens the heart and they often have news from away.

Each Tribal group of 50 or more will have a 5th level Fighting Man as leader, a Priest of 3rd level, and 50% chance of a 3rd level Magic-User (Arcanist) of appropriate background. 
Groups of 100 will be led by a 7th level character type plus 2d6 of Leveled NPCs. 
Groups of 150 are led by an 8th level NPC with 4d6 leveled NPCs and 
200 or more by a 9th level Lord character with 6d6 leveled NPC followers. Three of these will be "Sworn Swords", 3rd level Soldiers, fanatically loyal to the leader and always found at his or her side.

The Nomad tribes rarely use horses for beasts of burden or mounts, preferring instead the hardier Gurrath, a feathered bipedal reptile. Standing nearly ten feet tall, the Gurrath is able to carry one or two passengers, or a good load of gear, or even pull a cart or wagon (though this is usually the province of the Vorlup). 
Gurrath are vegetarians and have internal water bladders that hold several gallons of water, able to sustain them for up to three days between waterings. The Nomads have mastered the trick of the Gurrath young to get the mother to release some of that water for them, and can drink of this water at need.