Veigar is a really strong champion , but he is a hard champion as well , here are a few tips that i can give you to master veigar and have a 100% winrate if played correctly that is.

Veigar in my opinion is the strongest League of Legends champion (if played right).
Many people think the best position to play Veigar is mid-lane,and that is not totally correct, sure you can play Veigar on midlane but thats not his best lane. His best lane is top-lane, and here i will tell you why.
Veigar on mid can easily be killed with the help of a jungler, and because midlane is such a wide free space even the enemy can kill you more easily, but on top-lane you have the advantage , since its a smaller place you can get more dark matter and cs and if you are ganked you easily E and run away safely.
Don't focus on farming CS , sure CS is important, but on Veigar it's not the most important thing to do in lane, Veigar atacks barely scratch you in early-game, and farming minions is harder than normally and its eating your mana rapidly. The best way to play Veigar is to only use Q and focus on hitting the enemy champion with your Q ability, whenever you see you can hit the enemy do it, best case scenario is to get him and a opinion in one strike.
Although dark matter is important if you see 2 low minions in a line focus on those two, always focus on getting dark matter and CS.
Thats's pretty much it ,i think. Also if you play Veigar mid , dont be afraid of Zed you can easily kill him, trust me. He should be afraid of you!

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