User blog comment:Willbachbakal/(Champion Rework) Kassadin, the Void Walker/@comment-10958553-20150304160119/@comment-1330314-20150305005112

I think the problem with special-casing non-ult projectiles is that it would seriously affect clarity and diminish the overall gameplay of the mechanic: a Kass that destroys all projectiles would a serious and constant threat to maneuver around, including when using ultimates, and having ult projectiles ignore that lessens overall gameplay, I feel. I also don't want the absorption to cost mana, because absorbing projectiles should be purely rewarding: a mana drain upon destroying a projectile would, at best, punish Kassadin for playing correctly, and at worst it could completely screw him over when assassinating in crowds, where blocking projectiles should be most rewarding, and not punishing at all.