Concept for Void synergy in TFT

So, I personally think the Void buff is a little too strong with how easy it is to get (two tier 1 units and a tier 2 unit, can get online before you even hit PVP rounds) so I decided to come up with a concept for a new synergy buff for Void units.

The idea is instead of a bonus to damage, they get "Evolve". If you have 3 Void units, all Void units gain an additional ability.

Kassadin gains Null Sphere: Can gain mana, and at full mana throws an orb at a nearby unit. The orb silences for 3 seconds, and does magic damage.

Kha'Zix gains Leap: Passive that triggers when Kha'Zix gets a kill. Kha'Zix leaps to the furthest unit, dealing magic damage. OR Kha'Zix gains Unseen Threat: Kha'Zix deals bonus true damage to isolated units (functions like Yasuo's Exile buff, but this one lets him do more damage to them).

Rek'Sai gains Queen's Wrath: Passive that makes Reksai's auto deal damage in a circle around her (every surrounding tile).

Cho'Gath gains Feast: Feast makes Cho'gath's auto on targets below 25% deal extra true damage, and heals him. OR Cho'Gath gains Vorpal Spikes: Passive that makes Cho'Gath's autos deal AOE magic damage, like Tiamat.

I think this would work, because giving them an active or a passive wouldn't mess with the mana system at all, since Kassadin doesn't normally get mana, and the rest already have an ability. It also makes more flavor sense, since the Void is about evolving and changing. Could also raise the number up to 4 voids instead of 3 if this proved too strong.

Also, idea for a fifth void: Kai'Sa: Tier 3 unit. Void, Sorcerer. (Don't @ me, she's hybrid, and can totally be counted as a sorcerer if Kassadin can)

Ability: Icathian Rain: At full mana, shoots a swarm of missiles that deal magic damage.

Void buff ability: Killer Instinct: Kai'sa dashes to a nearby champion, at her max auto range and gains a small shield. Passive ability that only triggers when Kai'sa switches targets.