Can't help myself so have to post.
I don't like the new Kassadin lore, but yeah maybe they'll expand it later on but as it stands right now from what it was previously, I loved that he was a man that went into the void and came back out of it to fight the void and protect runeterra, it was purely that, he was the man that went in and came back something else.
I loved that his daughter is released but they stole kassadin's identity and gave it her. Hell Kassadin's entire concept and most of his kit was built around someone who turned the void into something to use to go around fighting and killing void monsters and the void's lackeys(Malz).
He was the man that came back, she was the lost daughter that made him do so. He went in to go after her and came back as something else: It was a beautiful story of a father that risked his life to brave literally hell and death to find his daughter and when he returned he was forever changed by the horrors and reality of the void and pledged himself to protecting Runeterra from it. His entire kit is based on the Void hell the naming of his abiltiies are based on the meaning of the word Void so now his entire identity is a man that got a ton of powerful artefacts and has never touched the void damages him as a character conceptionally speaking. That really didn't need to happen to release her as a champion.
Now that It merely killed his family and drove him to revenge like a bad Mel Gibson Movie hurts him as Kassadin. He WAS a cool character, he did something NO ONE else had done, everyone had been touched, damaged, corrupted by it but no living thing went in and came back out. HE DID that was why he was cool, both as a concept and character
But they might release a story that has him go in and fix this obvious tarnishing of him as a character to boost sales of Kai'Sa but right now the lore has changed from having entered the void and returned as "Kassadin" to earning the name kassadin by some of the most hogwash piece of writing I've seen in league champion lores and i dislike it.
Kai'Sa is an unoriginal poor man's version of what Kassadin was and no short story is going to change that.
Just my two cents