I wish we knew more about the Order of Shadows and Zed from Kayns story.

Zed was once an honorful student who, when wracked with jealousy, struck down his mentor and fled.

That is how i would sum up Zeds lore in 1 sentence. And through all of the pages of Ionian lore, as well as Zed showing up in SO many cinnematics, we dont actually know past this point to my knowledge.

Through Zeds and a few others we know what Zed did, through Jhin's story we know what Zed used to be. But there has been pretty much no information to him as a ruler of the Order of Shadows, that i can think of.