Kian would be lying if he were to say that he was not as curious as Sango about how they would both perform duelling with each other in this world.
So far, Sango and Kian's duel had always ended up in Sango's favour. Kian has superior control skills over Sango, while the latter's inherent ability to predict his enemy's movement is greater than the former.
Before Kian's class became the martial God, they had always duelled and often it ends in Sango's overwhelming favour.
The reason is that Kian's former class limits his range of attacks as well as the amount of movement that can be made in a second.
But once his class became the martial God class, he had at his disposal a wide range of attack methods that allows him to incorporate several movements from different branches and helps him to further create moves that are unique only to him.