Detailed Instructions: In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
Problem:Who is known to use Gur Khan?, Context: The next direct threat to Temüjin was the Naimans (Naiman Mongols), with whom Jamukha and his followers took refuge. The Naimans did not surrender, although enough sectors again voluntarily sided with Temüjin. In 1201, a khuruldai elected Jamukha as Gür Khan, "universal ruler", a title used by the rulers of the Qara Khitai. Jamukha's assumption of this title was the final breach with Temüjin, and Jamukha formed a coalition of tribes to oppose him. Before the conflict, however, several generals abandoned Jamukha, including Subutai, Jelme's well-known younger brother. After several battles, Jamukha was finally turned over to Temüjin by his own men in 1206.
Solution:
the rulers of the Qara Khitai