Just now realizing that Kassadin isn't really a Void champion
His only "Void" abilities are from the Void Stone he carries.
His passive is a Void Stone that collects magic energy.
His Q and E are releasing all that energy.
Those are his only "Void" abilities.
His W isn't a void blade, it's simply a null energy blade he stole.
His R isn't a void technique either, he's using Zaunite technology to Riftwalk around.
His lore says he's corrupted, but it's described as more of a parasitical virus than an enhancement. He's even using Zaunite technology to suppress it (his mask).
My life is a lie.
Edit: It makes sense though. It's unreasonable to imagine that some random human could just adapt to Void energy and manipulate it. This isn't the same thing as Kai'Sa, who integrated with a Voidling. Or Malzahar, who became a corrupted prophet of the Void and enacts its will.