Malzahar is a difficult playing magic/ranged champion. He has very strong spells and is a great
1v1 and ganker. Malzahar is mainly used for top/solo lane but also in partner lanes. His passive, summon voidling is very useful, spam your spells to summon lots of voidlings. I reccommend Malzahar for both 3v3 and 5v5. Malzahar is also a great minion farmer, as he kills them easy buy spamming spells.

I reccommend buying Doran's ring as the first item for its health, ability power and mana regeneration, as it will help your spell spamming. Next item is Mejai's soulstealer. It's a very good item for Malzahar, because he could hold his stacks pretty long as he could escape easy with Flash and Ghost. After that comes Blasting wand, for some ability power. Next is Boots of Speed, just for the movement speed. Then you upgrade the Blasting wand to a Rabadon's Deathcap,
for great Ability power. Then you upgrade Boots of Speed to Sorceress shoes, for movement speed and magic penetration. Next item is Rylai's Crystal Sceptre for the Ability power and Health. It's a great item for Malzahar as it keep his health stable and same time some Ability power.
Then it's time to buy Void staff, for it's Magic penetration and also for it's Ability power.
After you bought the Void staff, you should sell your Doran's ring, and buy another Rabadon's Deathcap. These items are definatly the best items for Malzahar.

If the enemy is not at your turret port back to base and buy your items and get ready for a gank. Tell a teammate(try to get one with a stun/snare or high dps) to come to mid and wait in the side bushes. Make sure your teammate is not seen going to mid by his laneing enemies. Have your teammate use their stun/snare and when they do run up and start your Ultimate spell rotation. If you have a teamate their all you need to do is make sure you get Null zone, Malefic Vision and Nether grasp off. don't forget ignite during your ultimate and possibly Call of the Void if they live. If you kill your mid lane oppenent have your teamate help by pushing mid turret hopefully doing some good damage to it. Keep setting up ganks against the person you are laneing against. Always try to have a teammate help so they can get stacks of mejai's if they have it or some gold for an assist. If the side-lanes are getting pushed hard setup a side-lane gank with your team and push back. You need to watch all lanes and decide where you can get kills and help your team push, just don't head for a side-lane right infront of an enemy or enemy minions. You don't want the enemy to know your comeing so back up a little bit then head to a side-lane for a quick gank. If your mid-lane enemy is a fast pusher like teemo, sivir, or twisted fate you might want to have a teammate from a different lane go farm middle while you go gank and push a side lane. Don't forget to finish your Deathfire as soon as you have enough gold too and grab Merc's and Rylai's ASAP. Try to keep mid on lock down and your goal is to get that first mid turret down.

Port back at level 6 and buy as many of your required items as possible. When you get back try to setup a gank with your lane partner. If your lane enemies are playing too defensively because you are pushing very hard or if mid lane is getting pushed hard you should head over to middle to help gank the enemy mid player. Remember to communicate with your team what you are doing, and make sure they know that your ultimate is a stun and who you are going to be targeting with it. Pull off your gank and push whatever lane you got the gank in. Keep setting up ganks with your ultimate and if mid lane or the other sidelane is haveing trouble try to setup a gank and help them push a little bit leaving your lane partner to keep pushing in your lane. Don't forget you are a pushing champion and you need to use your AoE/Curse as effective as possibly to help your team get to turrets and down them.

-You are a pusher, if your team is having problems getting past the enemy gate and downing an inhibitor try to push a different lane solo, just be very cautious and don't stick around for more then 2 or 3 waves of minions.
-Watch for backdoors your strong AoE's can help push a twisted fate out of your base and keep him at bay.
-Don't forget to stack curses when you are at a turret faceing off with the enemy team.
-Don't Be Stupid the more you die the less you are in the game, which is less time getting kills and gold.
-Try to use your Call of the Void over walls, the better you get at predicting movement the more crazy things you will pull off.

Malzahar is a very effective character and if used properly can help your team win. This is my first time writing a guide and I would love feedback on what you think about it. What should I include, takeout, or change. Tell me what you think.

I have played Malzahar a lot, and for this reason I chose these items. This build has proven quite successful to me.

As you start out in your summoning pool, grab a Sapphire Crystal and 2 health potions.
Remember to cast Call of the Void two or three times to get out your voidling for the next spell cast.

I usually take a solo-mid/top lane, as Malzahar excells in this area.
At level 1, harass once with your Call of the Void, and then start last-hitting and farming.
When you reach level 2, you will have your main farming ability, Malefic Visions.

Depending on the situation, you can do the following.
For a high elo ranked game, make sure you don't push with your Malefic Visions
Harass your enemies with your E.

For a normal game / low elo game, it doesn't really matter about pushing. Just make sure you don't push too far.

As you reach level 6, your enemy would probably still think you're playing defensively. Just simply land a spell combo Q E W R Ignite / Flash + Ignite. Kabam, A kill / first blood.

As you reach mid game, make sure to ask your jungler if you could take a blue buff / take the enemies blue buff. Malzahar's role in a teamfight is to constantly nuke the enemies, so taking a blue buff would help out A LOT.

In late game, if you have all of your items, then you will do crazy nuking. Make sure to not overextend and let them kill you.

In a teamfight late game, always appear after an ally initiates, or use your ulti to initiate. Never get targeted or focused, as you are a squishy caster. You should constantly try to harass with your Q, W, and E. Always focus the squishy on their side. By using your abilties a couple of times, the enemy squishy would almost die. By using Malefic Visions and Ignite, you would get a simple kill.

Remember, in a teamfight, YOU are the squishy. Don't get focused in teamfights, lose, and blame the loss on my build. The purpose of a squishy AP Caster is to kill out the carry.
I have seen many people fail with casters, the reason being overextending. You aren't a tank or a tanky dps so don't charge in. Simple as that.