So yeah.. Here's a Vel'Koz rework that would make more sense than his current kit. (At least to me)

I know it's early but really I hate his kit and I think this kit (the passive for sure) suits his character more.

Passive: Knowledge

When an enemy minion, champion, or neutral monster dies near Vel’Koz, they drop a bit of knowledge. (Wolves, wraiths, and golems drop 0.5 knowledge points, the Wight, blue buff, and red buff drop 1 knowledge point, caster and melee minions drop 1 knowledge point, dragon and baron give 3 knowledge points, and champions drop 5) For each stack of 3 knowledge, Vel’Koz gains (2.5% of current AP) in ability power and (3% of current MR) in magic resist.

Q: Transform (Passive-Active)

When activated, Vel’Koz’s auto attacks begin to ‘transform’ enemies to become void creatures. Each auto attack costs 10 mana and does bonus magic damage each hit.

W: Plasma Fission

Vel’Koz fires a plasma bolt that slows and damages the first enemy struck. Once Plasma Fission hits, reaches its maximum range or is reactivated a second time, the bolt splits at a 90 degree angle. The split bolts deal the same damage and apply the same slow.

E: Void Stare

Vel’Koz sends out a ball of void energy from his eye that opens upon hitting an enemy champion. Once opened, it deals magic damage over 2/3/4/5/6 seconds, then closes and applies knock-up.

R: Life Form Disintegration Ray

Vel’Koz channels a ray of infinite energy that follows the cursor for a brief while, damaging, and slowing all enemies hit.