Three months after the stone tablet with characters of ancient Qidan was found, the Fourth Prince Wanyan Su set off with his mighty troops. The leading troop was cavalries which had gone through tough training. The troop was awarded by the Grand Khan of North Di. Wanyan Su arranged this troop at the forefront, which was not only very imposing but also useful for the removal of mines when crucially necessary.

"The removal of mines means that if there were some dangers, the troop ...