As you know people tent to think that Wuju is a Blade only Martial Art since Yi is the last member of it. Here im gonna talk a bit more about Wuju, as far as i have understanded.

What is Wuju?

Wuju is an Art that focuses on learing Spiritual control and awereness of ones spirit as well as the enemy's. SO you could say its like the manipulation of chakra in Naruto and other "spiritual enery" based powers (Ki anyone).

As far as RIOT has explained Wuju was an Old Martial Art whos member where killed "recently" (say recently since i time continuity in LoL is not really explained) by Noxians, if i remember well an Journal of Justice mentions that it was a Toxic bomb assault led by Singed and Warwick.

And so Yi was left as the last member of the Wuju, whit Wukong as his new aprentice.

Diferent styles:

so far there are two styles of Wuju combat:

- Blade master: Yi is the Blades man of the Wuju meaning he is the Master of the Blade Wuju style. Since Yi is teaching Wukong the "Art of Wuju", and since WU uses a staff and not a blade, its suggested that MAster Yi is also well versed in other weapons as well as the sword or at least he know some of it. Maybe Yi is a better fighter than people give credit for.

- Staff Master: So far Wukong is the only Staff user of the WUju style. Mind you Wukong original name was Kong and he was a skilled fighter from Kumungu Jungle and changed his name to Wukong in honor to the Wuju tradition.

In the wiki of Iona says that Master Yi has more aprentices so who knows maybe we will see more Wuju users in the future.

(gonna add more later)