Welcome, summoners!
As you can read in the topic, this guide will introduce an aggressive AP carry build for Malzahar, my favorite caster in League of Legends. My aim is to sum up all the necessary information you need to have fun and success with this character in a short and easy-readable style.
I don't like to go too much into detail because i know that the best way to learn a game is playing it. I just want to point out the most important facts in brief words, so you can have a look at this guide when the game is even already beginning or running.
Feel free to try some variations and to develop your own style of playing. I'm always happy about feedback and criticism!

Why should you pick Malzahar?
Malzahar is a powerful caster that deals an enormous amount of damage. He can play an important role in team fights and also deal with nearly every 1vs1 situation. Though he is a late game carry, Malzahar ist also awesome in early and midgame. His ultimate is simply amazing.

Pro's
- Each of his spells is useful
- Deals very much damage if he has enough AP
- Nether Grasp can be used to initiate a gank
- Malefic Visions can be used both to harass and to farm
- Call of the Void can silence groups of enemy champs

Con's
- Few HP, easy to gank
- Needs lots of mana in early game
- Needs some skill to cast Call of the Void

Laning
As a carry, Malzahar should take the mid lane to get more gold and experience in the laning phase. All time and item specifications given below are based on this idea. But remember, League of Legends is a team game, please make sure that your mates agree with you.

Idea behind the item build, runes and masteries
I noticed many summoners picking Rod of Ages, Archangel's Staff and so on with Malzahar. Sure, with this setting you can solve your mana problems and get some more hitpoints to be a little less squishy and to enjoy a smoother gameplay. But remember: Each item must be paid, and you have not enough gold to make all your wishes come true. So you have to make a decision. I decided to play Malzahar as aggressive and devastating as possible. For this reason, it is your first priority to get as much as possible:
- Ability Power (AP)
- Cooldown Reduction (CD)
- Magic Penetration
This is the most important idea behind this guide and you should have it in mind when you invest your gold into items. Anyway, it is not possible to max the whole power out of your abilities without some mana regeneration. I will discuss this problem in the further parts of my guide.

Runes
- 9x Greater Mark of Magic Penetration
- 9x Greater Glyph of Scaling Cooldown Reduction
- 9x Greater Seal of Scaling Mana Regeneration
- 3x Greater Quintessence of Ability Power
The Marks and Quintessences are used to improve your damage and magic penetration even more. Cooldown reduction is useful for spamming Malefic Visions and to get back your Nether Grasp as fast as possible. To reduce the mana problems i decided to use Greater Seal of Clarity, so i don't have to buy much mana items (see basic idea).

Masteries
See scheme at the top of this guide. It is important to have magic penetration and cooldown reduction from the offense-tree (see basic idea). All other points are put into utility for increased mana regeneration.

Summoner Spells
You can either pick Ghost or Flash as your escape/chasing-skill. I personally prefer ghost, but i can't really explain why. The second spell should be Ignite, please remember that you are playing an aggressive style. Ignite stacks with Malefic Visions, with this combo you can easily kill every escaping enemy. Don't forget that Ignite reduces health regeneration, which is a must have against Warwick and other champions based on lifesteal/regen. I would not pick Clarity - It may be useful in early game but is completely **** when you are at higher levels.

Core build summary: Sorcerer's Shoes, Morello's Evil Tome, Mejai's Soulstealer, Rabadon's Deathcap

Usually, i start with Boots and 3x Health Potion. I like to have the movement speed bonus at the beginning, so i can poke out and harass my opponent with Malefic Visions. Furthermore i can escape early ganks and i feel more comfortable against very mobile champions such as Vayne. Some people prefer Doran's Ring as starting item, but i dislike to buy an item that i have to sell later on. Also don't underestimate to have Health Potion, which means that you can stay longer on the lane, making more gold and experience. If it is a must have for you, you surely can buy Dorans's Ring, it won't ruin your build.

The second item will be Fiendish Codex. This item will provide the needed mana regeneration to cast Malefic Visions constantly. It also has a bit AP and cooldown reduction to improve your early game aggressions. Note that Fiendish Codex will be your only mana item (see basic idea).

As every stack-item in League of Legends, Mejai's Soulstealer has to be a deliberate choice. You have to spend 1235 gold for only 20 AP in the beginning, which leads to a sensible disadvantage compared to your opponent. But if you are experienced with Malzahar and if you are able to make some kills without dying yourself, it will soon pay off. And, as I told you..This is an aggressive build. :) Many people prefer to get the Soulstealer as the first item, but i don't see any sense in this decision. Before you can make kills with Malzahar, you first need some basic movement speed and mana regeneration.

After that, you can upgrade your Boots to Sorcerer's Shoes for some extra movement speed and magic penetration. Also, upgrade your Fiendish Codex to Morello's Evil Tome to get more AP and increased cooldown reduction. You will now be able to cast Nether Grasp more often.
Note: If playing on the mid-lane, you should have completed this basic build after 15-20 minutes and you should then have about 120 AP, dependig on your stacks on Mejai's Soulstealer.

This item is a must have for Malzahar. Try to farm it as soon as possible, you should have it until the 30-minute-mark! With about 10 stacks on Mejai's Soulstealer it boosts your AP to ~450, giving a ~600 damage bonus to Nether Grasp which deals now ~1100 overall damage. It also improves your other spells and makes the combo of Null Zone and Nether Grasp deadly for all champs without magic resistence.

Late game items

From now on, the further item decisions depend on the situation and the enemy team. Let's have a look at your possibilites:
1) If everything is going fine and you are ruling the game, i would recommend you to continue your aggresive build and buy a Rylai's Crystal Scepter, followed by a Void Staff. These items continue to increase your AP to over 600. The magic penetration is necessary to deal more damage and to shred enemy tanks. I really like the passive ability on Rylai's Crystal Scepter, it is very helpful to chase enemy champions. Last but not least, the 500 health bonus will increase your survivability in lategame.
2) If the enemy team has heavy casters, such as Veigar, Annie or Brand and you die quite often to their spells, it would be better to purchase a Abyssal Mask for some magic resistance and more AP. After that, you can decide either to continue with Rylai's Crystal Scepter or Void Staff, or you can buy a Banshee's Veil if it's still not enough magic resistance.
3) If the enemy team has heavy AD/Critical Strike, such as Vayne, Ashe, Master Yi, Tryndamere and you die quite often .. Get a Zhonya's Hourglass to increase your armor. Don't forget to activate it!

Items not to buy
As i told you before, i wouldn't recommend to buy mana/health-based items such as Archangel's Staff or Rod of Ages.

Early game (0-15 min)
In my opinion, the most important skill in early game is Malefic Visions. It jumps from target to target (if the target dies in time), regenerates mana and deals a good amount of damage over time. Use this ability in combination with your autohits and your passive, Summon Voidling, to make as much last hits as possible (farming). Remember that your Voidling prefers to attack the target which is enchantet with Malefic Visions. Use this to your advance and harass the enemy champion constantly, forcing him to use health potions or to teleport back to base. If the enemy is low on health, you can also try to poke out and make a kill. Ignite and Call of the Void will help you here.
You may have some mana problems at this time. Because of this, you will need to buy Fiendish Codex right after your Boots (see item section). Also, i don't use Call of the Void when i'm not sure that i need it to escape (silcence!) or to make a kill. If you are low on mana or on hitpoints, don't hesitate to teleport back to base, i don't see any problem here if you don't overdo it. When you come back to your lane and the enemy is pushing your tower, you can try to walk through the river and attack him from behind. If he gets stucked between you and the tower, you can sometimes make a kill easily.

Midgame (15-30 min)
Your core item build should now have been almost completed and the next step is to get Rabadon's Deathcap as soon as possible. This item will boost your AP and increase the damage output enormously. You should have a look at the other lanes as often as possible. The time has come to help out and to try some ganks with the aim to get more gold and to gather stacks on your Mejai's Soulstealer. Always try to grab the target enemy with Nether Grasp when he is standing over your Null Zone. You will need to pratice this a bit, but it will be very effective. Don't forget to farm further, you can now also use Call of the Void for this task.

End game (30 min until end)
The further item build now depends on the situation (see item section). Try to make as much kills as possible, you should now deal a lot of damage if everything went fine so far. Remeber that you are squishy and that enemy carries are also getting stronger. Stay stucked with your team and use Call of the Void and Null Zone in team fights to damage multiple targets. Malefic Visions and Ignite can help you to take down escaping enemies.