Here''s a fix to your boring void story @Riot. You're Welcome.

Kassadin Kassadin is a caravan guard with a family. (I nailed that long winded bio with a sentence, you're welcome) who ran afoul of the void where he and his entire caravan was consumed by it. Kassadin's mind was consumed, his family was the only thing keeping him going. He got out and could only remember his family and that he was a guide through danger. Kassadin then became the only fitting name he knew, for he braved the greatest danger at some expense to his sanity. (That lame name now has purpose, you're welcome again.)

Malzahar Had a good story. Keep it. Add that he thinks the void brings enlightenment, and hearing the rumors of a man going there and returning makes Malzahar believe he has an enlightened cohort. Kassadin obviously refuses the "gift" which makes Malz angry, so he attacks the only thing that saved Kassadin, his family. Serves to add conviction to Kassadin.

Kai'sa Years have passed since Malz and Kassadin had their conflict. Growing up in the void has left Kai'sa fragmented. In a mix between madness and the only friend she's known, her personality is weird at best. She talks to herself and her suit. Each tries to impose themselves on the other. The suit is still a consuming voidling. It should still try to meet those goals. Kai is still a human, she should be in conflict to reign in the suit. It is her ONLY friend though.