Tweaking his ult is not going to fix Veigar, and in all honesty I do not think his ult is the problem. Veigar's primary issue following his "compensation" is a lack of reliability. Whereas before any reasonably competent Veigar could stun a target of his choice with a well-placed Event Horizon, now it relies on crowd-control from a teammate, enemy mistakes, or precognition to land. Coupling that with Dark Matter being extremely difficult to land without any form of crowd-control, and The Tiny Master of Evil essentially has half his kit available to him at any given time.
Veigar has no significant aoe damage. His Baleful Strike can hit two targets at most, his Dark Matter has a very small area of effectiveness, and Primordial Burst can only strike one target. So why is it that a champion who can only efficiently damage one enemy at a time has less reliability than other mages?
Here is Veigar's problem in a brief example:
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Veigar traps an enemy in his Event Horizon. He can either drop Dark Matter on their heads and hope it lands, which it likely will not, toss a Baleful Strike and hope it connects, or walk away to try again later.
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Vegiar stuns an enemy and can drop his full combo. If they are at full health, they may survive. If not, Veigar has successfully made a kill.
You either land your stun or you don't. That is not fun. How sad is it that even when you do trap an enemy in Event Horizon it amounts to nothing? They can still dodge skillshots, they can still shoot back.
Event Horizon or Dark Matter need to be changed in some capacity. As they are, these two abilities do nothing to enhance Veigar's gameplay.
Let's make evil matter.
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