Kai'Sa Confirmed as Kassadin's Daughter in League of Legends

Though this comes as no surprise to speculative League of Legends fans, Kai'Sa's parentage has been confirmed. She is Kassadin's daughter. Kai'Sa's voice lines can be heard now that she's available in the PBE. She has a few special interactions while one of them is with Kassadin.

When going up against an enemy Kassadin, Kai'Sa will say that he's familiar and then, most obviously, when she respawns will remark, "Father?" In the updated lore, Kassadin's daughter was lost in the Void, but we have yet to figure out why. In the past, it was because of Malzahar. While it's no longer explicitly stated, it does seem that Kai'Sa is tied to Malzahar. Upon killing an enemy Malzahar, Kai'Sa states, "I forgive you, Malzahar, but I never forget."

Fans can only hope that this lore will be clarified and expanded upon in the future. Plus, there's now the potential for some Kassadin and Kai'Sa father-daughter skins.