What if Veigar's Event Horizon actually worked (sorta) like a black hole?
What if those caught inside would be pulled toward the middle but not necessarily stunned, knocked, or otherwise disabled unless they hit the center where they will be stunned. Like, if they were fast enough (Yi, Hecarim, or anyone with a significant speed boost) they could "outrun" the pull so to speak, but slower targets such as the mages he's supposed to bust get pulled toward the middle where he can drop some Dark Matter on their heads and finish them with his ult.
Just an idea I had, thought I'd share.
Doodle demonstration because I'm terrible at drawing (rito pls hire)