Kai'Sa + Ghost Poro Unintended Interaction
So I noticed this while playing bots, but if Kai'Sa is equipped with the Ghost Poro rune (I had it as a splash rune with Press the Attack keystone); Ghost Poro, regardless of whether it's actually active, will be considered permanent AD towards Kai'Sa's Q evolution.
I haven't tested this with her AP evolution or with a Domination keystone, but I'm certain that this is definitely unintended on multiple levels.