The Kara Khitai are a Central Asian tribe whose main property is lack of honour. They troll Genghis Khan by stealing sheep and hiding Kushluks. They are the primary antagonists of the second scenario of the Genghis Khan campaign, and also secondary antagonists of the first one, after Ornlu.
Lack of honour
Unlike all the other tribes dicking around Mongolia, the Kara Khitai have no honour and no intention of ever getting one. They hang around the steppe with their cavalry archers and towers and GODDAMNIT IS THAT A MANGONEL? WHAT KIND OF A PSYCHOPATH WOULD EMPLOY A MANGONEL TO PROTECT A BUNCH OF SHEEP. I mean seriously.
Later they team up with Kushluk to destroy Genghis Khan's favourite tent. The tent is apparently the source of Genghis's powers because destroying it totally buggers his plan for world domination. Understandably, the plot is considered honourless something fierce.