If 
is the Master of Shadows, and 
is the Fist of Shadow, then is she Zed's fist?
Is this a parallel between 
being the Aspect of Twilight, and 
being the Eye of Twilight, thus Shen is Zoe's eye (why do you think they're different colors? Shen is the blue one obviously).
I believe that Zoes title as the aspect of twilight is an metaphor for her being the aspect of change. Twilight being the moment when the sky turns from day into night or in reverse . Change in the sky...
The Fist of Shadow is a title within the Kinkou Order for the one that's tasked with "Pruning the Tree" (as far as I can tell atleast).
Since she isn't part of the Kinkou Order any longer, she isn't the Fist of Shadow any longer either (hence, why her title was changed from "The Fist of Shadow" to "Rogue Assassin").
Riot's solar obsession has seem to infected the Kinkou as well
"Zed’s transformation of the Kinkou into the merciless Order of Shadow was almost complete. But, as the new Eye of Twilight, Shen intended to rebuild what had been lost. They would return to the Kinkou’s three fundamental philosophies: the pure impartiality of Watching the Stars, the passage of judgment in Coursing the Sun, and the elimination of imbalance by Pruning the Tree. Even though they were now few, they would train neophytes to restore and grow their numbers once more."
Shens' duty is Watching the Stars and Kennens' is Coursing the Sun
Was it always like this?
