The nomads are a long-suffering race. Their existence has been tolerated (barely) by the last fifty emperors since Emperor Meziz signed a covenant with them, allowing them to subsist on the banks of the infertile southern rivers in return for a small tithe. They are shunned by the folk of the Empire, and heckled and spat at in the marketplace. People only buy their meat and produce because it is so cheap.

Possibilities:

1. A character commits a crime or contravenes a taboo and is outcast by the nomads. S/he must make a living for s/himself in this hostile world.

2. The characters are on the ruling body of the nomads. The emperor starts a policy of persecution against them and they must either resist or flee.

3. The nomads try to make new gains of territory and have to journey to the capital city across the desert, with its terrible perils, to deliver a supplication to the Emperor.

4. The characters are an elite group of nomadic thieves who steal from farmers. However, to draw suspicion away from the nomads, they go around distant regions, disguised as locals.

?