New Zilean Innate: Temporal Anomaly

You know why Zil is so awful?

Well, aside from losing all of his long range, reliable damage.

It's because of how hastes and slows are applied in League. So how about something that breaks the mold, provides Zil with a unique form of support to add, and gives him an Innate that actually does things?

Temporal Anomaly: All speed-altering effects on enemies and allies within (aura range) of Zilean are altered. Slows on enemies now stack additively, rooting targets slowed by 100%. All hastes on allies stack additively and ignore movespeed diminishing returns. The Temporal Anomaly de/buff lasts for (duration) after moving out of aura range.