This is the malzahar build I mostly use, it has great survivability and damage output.
This build will get you tons of HP and AP at the same time, focusing on getting survivability and AP items at the same time to get the ideal balance.
With the complete item build people will not even bother focusing you since of the hp,armor and magic resist you will almost be an off-tank with a great damage output and cc.
Pros / Cons
-One of the best ultimates for 1v1
-Rocks late game
-Only 1 escape mechanism
-Not as strong as a pure AP build early game
-Susceptible to cc
Note: The build is expensive but by the time you get rylai's you should be owning.
I take flash and ignite for easy kills early game.
Ignite combined with your malefic visions and ultimate is most likely a kill
Flash can be used as an escape tool as well as a gap closer.
You could also change ignite for exhaust if you feel like playing passive it's a great life saver and it has great cc.
I max malefic visions first because it's a great farming and harassing tool, if you have full mana don't be afraid of dropping it on the enemy champion for some damage, if you are running out of mana just push it through the minions and with the help of runes you will be back at full mana again.
The reason i max Call of the Void instead of Null Zone is because the damage output from Call of the Void is faster, some people prefer to use the full freaking combo ( CotV,NZ,MV+Ult ) but by the time you set it all up they'll end escaping so i wouldn't even bother.
A well placed CotV + MV + Ult should be more than enough to get you a kill if not just use ignite.
The only reason i would max Null Zone first would be if i'm against 2 offtanks and a tank.
If you are looking for an early kill, and you have your voidling ready ( Voidling is very useful but most people don't notice it ) flash in, use Call of the Void, Malefic visions and Ultimate, try using the 3 of them as fast as you can so your ultimate suppresses them while Call of the Void is activating, if they don't die with that an ignite should be more than enough.
If you already have your rylai's you might as well try your full combo with null zone.
Late game null zone is really strong so don't ignore the fact that you have it, I just wouldn't recommend using it early game.
Farming is in my opinion the most important thing in a game and it's a piece of cake with Malzahar.
Go mid so you can have all the minions for yourself.
Don't bother using your Malefic Visions until the skill is level 3 because it's hard to push and you only waste mana, once it's level 3 try to get it to your enemy champion, you can do so by dropping it in one of the mage creeps and kill them all at once with your call of the void so malefic visions transfers quickly at the enemy champion.
Try to get your voidling out every time you can to help you push malefic visions.
Don't drop Null zone on the creeps cause you are just wasting mana, the damage will be minimum.
I graband 3
You can also grab but it only gives 100 Hp, 1 potion is equal to 200 hp so the potions will help you last longer in the lane, you don't need the mana regeneration thanks to your malefic visions passive, just don't spam skills, use it smartly.
Gives you a bit of everything, HP, Mana and AP, I suggest rushing it so you can max it as early as possible.
With this and maxed rod of ages your hp at level 18 will be around 3k, the best thing of this item is the slow, you can easily chase enemies with it and it gives you more time to place your combo.
With a good amount of Hp and AP rabadon's will boost our damage output significantly.
[Note: take this if focused by AD carries] This item will not only give you more AP, but also defense, with this item's passive and armor bonus staying alive in teamfights is a piece of cake.
For my last item I usually go for the passive, bonus movement speed, AP and magic resist, the passive will help you push turrets in 3-5 hits, but if they are getting a lot of magic resist I would recommend .
I would insist you should get instead of , why?, because void staff gives you more penetration for the tanks, if you want abyssal for the magic resist, then you should rather go lichbane.
The reason i don't take any mana regen items is because malefic visions allows you to regain your mana simply by farming, note that if you just spam it randomly you will not be able to push it through the minions.
At low levels try hitting every melee once then cast MV on the weaker one.
This is just my play style, I usually dominate mid with it and feel secure of getting away from ganks so I thought maybe you guys wanted to give it a shot, Good luck.
Sorry for my grammar and please give me some feedback.