Hello, my name is DarthJonhy.I play in EUW and I'm in Gold Division, main Veigar. I decided to make this build because this AWESOME! Mage is completely overrated.

Veigar is a High Nuke Magic Damage Dealer, the best in all League of Legends.

Pros
Best Nuke Damage in game
Awesome Late Game
Event Horizon Is very useful to control teamfights.
Destroy Squishy Targets, tanks too btw

1.Low Range
2.Very Very... Bad Early
3.No escape ability expect Event Horizon

1.If your team has good engage and tanks, this problem is easy to solve. Just follow your engager. If the enemy team engages try to catch someone in Event Horizon and DESTROY THAT TARGET.
2.Just farm with Baleful Strike and play safe in early.

3.Stay Inside of Event Horizon and RUN AWAY!. Cleanse and ghost can help you to escape.

Flash and cleanse are the bests spells for veigar (in my opinion) but you can always take ghost to escape from ganks quickly. Cleanse is really good for Late Game/Team Fighting.

Play Safe and farm with Q, trying everytime as possible to kill two minions at once. You can farm and poke easy just kill a minion with your Q and hit the champion with that Q too.

Always Ban Fizz!You can carry games really easy with veigar just take care of engagers in enemy team.

I'm Working to finish this guide later. Update soon.