New summoner spell: Inhibit

With the mobility creep looming over immobile champions, there needs to either be a massive mobility nerf, or a counter to mobility.

Inhibit- Inhibits all dashes, blinks, teleports, and leaps by target champion for X amount of time. ( does not apply to thresh's lantern, or flash)

It should have a low cooldown( for a summoner spell), and have a moderate duration( 5 seconds?). It should have an internal cooldown to prevent chain inhibits on a single target.

Thoughts?