My typical summoner's spells are ghost and flash. Flash ,becasue it's a typical for unmobile champions and ghost ,beceause it help you then you're without flash to run away from danger or secure a kill with extra movement speed.In games with high risk of losing lane i play with exhaust. But sitll if you like playing ignite or teleport you can still do it ,becasue ignite make easier to kill targets at lv 6 and teleport for roaming ,backing faster to lane or roaming.

There's to types of builds and only changed item is first (full item). At first back buy last chapter for mana (you will sell it later). Fisrt rush item is abbysal or zhonya's. Abbysal when you play vs ap mid and you can lose or the most of enemy team is ap. Build zhonya's if enemy midlaner is ad or thay have one-shot combo. Second item is Nashor tooth. We build this for cdr's and aa small buff for easier aplaying thunder lords and easier farming (no need to use more aa and tooth scales better in late than morellonomicon). Third item is Lich bane (for 45 % cdr and aa ap dmg [which works great with tooth ,becasue you will do fater aa animation]). I like to buy echo as my forth item (but you can swap rabadon's faster and than echo) for a lot of ap and more dmg (echo balls of dmg). And last i build rabadon's becaause it just give you tons of more free ap. Buy boots before third or forth item.

First I max q for easier farming, e second beceasue it's easier to aa someone plus if they buy mercurial boots you still stun them for long time and w last ,because i prefare do a aa than w (aa would deal more dmg) and you can hit with w only when someone is stunned with e at 95% of the time.

I choose like this ,becasue you can melt someone in lv 6 (bigger chance to noe shot when you play ignite) plus for max cdr becasue it's always usefull in every moment in the game.I prefare thunder lords than deathfire ,becasue you use more like one shot combo than poking into a kill.

Typical mage runes but with changed resist from flat to scaling with level because mages are stronger in late than early.

I do really long vs champions page in my guide before so it's good to check it out ( i'm to lazy to write it again + i'm new to this website and i have some preblems when i try to do my guide better ) Link: http://www.mobafire.com/league-of-legends/build/my-favourite-build-on-veigar-6-17-487305

Pros:
-High dps
-Good in low ranks and can be really good at higher ranks when mastered
-Really helpfull for team
-You can win every match up (if you will outplaying very good)
-Can be played at top, mid or support
Cons:
-Easy to kill
-When he is behind he don't deal dmg
-He sometimes must leave team to get some stacks

You can use w in early to get some creeps and just stacks some ap with q. In laning fase try to hit two minions or minion and champion to get the most of stack (and some poke when hitting champion).

If team can saving Veigar he can do so damn much dmg and apply a lot of cc and dmg (q can hit two champions ,w can hit even five champions and e can stun 5 enemys.