This is my first guide i hope you enjoy, if you have any question post it here i will answer thx everyone for reading.

Here is where the fun starts, You can litterally kill enemies fast with your combo you are going to buy your 2nd or 3rd Rabbadon death cap so you have around 600-800 AP enough for a kill.
If you meet a tank with alot of magic resistance you will probably suck, so wait until the 3rd Rabbadon and you can kill even the Tank, remember to Harrass take them down with some Baleful strike and when the tank is like 3/4 hp start with the combo and you will get a kill

Now you have all your skills and you are ready for some team fights and kills, as possible Stun your enemy with event horizon and go with your Combo, is a sure kill if you have the Deathfire Garsp, if not you can do this anyway but probably you will not kill a tank.

OK you have your dorans ring go on and Harass and get the last hit with baleful strike!!!
Do this until Level 8

Dorans Ring : great start with ability power
Tear of goddes : Keep you up with mana for farming
Mejaj Souls stealer : burst your ability power
Deathfire Grasp : For your Combo.
Rabbadon deaths cap : Buy 2 hats, then sell the Tear of goddes when you have enough money for the Needlessly Large Rod and then build an hat, you dont need anymore mana regen.

If you aren't good with the Mejaj, use Haunting Guise,20 ability power and 20% spell penetration really good if you are not good with the Stack items.

This combo will make kill every champ in just 3 sec!
1st usethenafter this useThenand finally
Master in the use of Event horizon so you can stun them then the first skill who will do damage will be Death fire garsp then the Darkmatter and instantly the Primordial burst and the baleful strike after, this will do INSANE DAMAGE!! 100% death.

Veigar is a little 1shotter machine, so i put just Ability Power and Magic penetration, just in the seals put some Cooldown Reduction.

1.

Baleful Strike

, use it to give the last it from level 1 to 18, use it like no tomorrow! No matter how much mana you waste use it!!!
2.

Dark Matter

is HUGE! use it in combo with the Event horizon!
3.

Event Horizon

is what makes veigar able to kill people in 2,5 sec even TANKS!
4.

Primordial Burst

= Death.