Idea for Veigar rework: an "Event Horizon" that blocks enemy vision (similar to a black hole)

Idea: instead of balancing Veigar by giving him insanely high AP ratios, infinite AP scaling, and mega execution damage - you cause an enemy trapped inside of Veigar's Event Horizon (E) ability to lose vision of their surroundings for the duration of the ability, and/or cause the trapped target's allies to lose direct vision of their team member, making it impossible to assist them with directly targeted support abilities unless blinking into the Event Horizon. (Minding that if this change were to occur, the rest of Veigar's kit would need re-balancing to make sure he didn't break the game balance)

Thoughts?