Okay, first off hello, this is Badmamajama dropping my first Malzahar build guide and I hope you enjoy it. I know there is many improvements I can make to this build because of its straight forward simplicity but I insist you try it out because this build hinges completely off of situational awareness, picking the correct target and "straight up skill."

Everything about this build screams that you will get your face blown off, which is very true but in skilled hands its lethality is unmatched.

1. The usage of Mana pots and health pots are mandatory for this build with or without support, while I did not include any in the item list besides the starting set of one health two mana Malhazars farming capability allows you to farm up an extra chunk of change for them easily. Malhazar is squishy, no doubt about it and through skill and the usage of pots you will come out victorious. Later game you'll "feel out" when you don't need them anymore.

2. (Items) Key areas of interest:
The initial build of boots and pots is straight forward so I wont go into that I'll skip straight to the good stuff.
I cannot stress enough the need to obtain "The Tear of the Goddess as soon as humanly possible after your Sorcerer's boots as to allow time for it to increase your mana pool based on kills, also it will immediately decrease your need for two mana pots to one if any.

*I have found it useful against more skilled enemies to add a doran's ring after you obtain your sorcerer's boots to bump your AP up to 30 but if this can be avoided do so because the tear of the goddess is a mandatory builder for your endgame mana pool*

Void Staff: the beauty behind adding this piece now is the fact that its components add AP as your building it allowing you to maintain a massive damage presence in your team, then upon completion your effectiveness against all enemies skyrockets.

(DUH, Rabadon's Deathcap is BADASS!) enough said about that.

Will of the Ancient's: this is probably a little weird for most of you to see in this build but I have to use it always, I have a dedicated couple of friends I play this game with, one being an absolutely lethal Ryze, and I believe that any AP based damage Champion should consider his teammates in his\her build because honestly we all do amazing damage and I believe one piece sacrificed for better team survivability and damage output should always be an acceptable choice. *secretly, shh dont tell my team, the 25% spell vamp helps keep my squishy *** alive.*

Lich Bane: this is for one reason only and is purely optional, I have this to sneak push towers, Malhazar can blast through waves of minions very quickly which makes him ideal for this tactic, lets say late game your team is doing well in the team fights and is causing a big ruckus in mid or up top, you back off and recall, after informing your team of the tactic of course, using your Teleport, you port into some of your mobs on bottom lane and with an alarming speed only capable by Malhazar you carry your minions to the enemies turret and having Lich bane allows you to spam out Call of the void making you do somewhere around 600-800 dmg to said turret after each cast, this will down turrets before the enemy team knows what just happened.

Okay, I'm sure based on damage output and farming usage I'll get a little flame for this but I find that rarely using this ability is for the best. In my honest opinion it needs an overhaul by Riot, it's damage is fine, its silence is invaluable as a defensive tool, but its functionality is pretty useless. I could see something with these traits having sick crazy damage because its kind of a pain to get where you want it or at least "slowing" and silencing the targets caught by it, yet I find more often then not I only use it as a hardly functional defensive tool against casters and support and a decent farming tool at later levels. Everybody knows that mobility is key to this game so having an ability like this makes it essentially useless, as for farming... come on... the last champion that could possibly have use for a secondary farming ability is Malhazar, because Malefic Visions is all that is needed in that department. Granted with considerable skill it is quite an effective defensive technique against bots but as for real players, they just avoid it if you don't miss all together putting it in the right place. (suggestions) This move should have a second or two where as it stays up, so anyone moving through it will be effected at least by its silence if not the damage. It could also be just ever so slightly expanded and given an arc so that more targets in its curvature could be effected. Anyways thats just speculation, go try it for yourselves and I'm sure you'll come to the same conclusions. Anyway you look at it it should be used as a defensive technique to stop support from silencing you or to get the always present blast damager from getting you before you retreat if you don't miss.

Here's the ridiculous stuff,

Malhazar can deal so much damage it'll leave you salivating in your chair and it'll leave your opponent slack-jawed in a pool of his own tears. It takes skill and finesse though which is why many people shy away from this champ because honestly a Ryze or Brand or Annie is just easier.
Think of it this way, Brand, Ryze and Annie are all glass cannons fragile but deadly, Malhazar is a glass flame thrower, your can do horrific amounts of damage but you have to keep the spray on them and it takes some time. You keep the heat on too long and you'll crack.

So here's the early game combo: Malefic Visions, arguably one of the most deadly dots there is, not enough by itself to kill but when layered with ignite at the correct time its effects are heinous to say the least.
Level 2: poke your opponent down to about 2 bars of health, drop Malefic visions followed by Ignite and watch them die simple as that.
Level 3: drop Null Zone "behind" target followed by Malefic Visions and Ignite and watch them impulsively run through your Null Zone to their death.

Now for the finesse and skill portion, Later levels allow the usage of you NASTY Ultimate Nether Grasp, which suppresses your target insuring that they don't get away while doing considerable dot damage.
Here's the rotation:
Malefic Visions - Ignite - Null Zone - Nether Grasp//crunch the numbers yourself just like I did and you'll be surprised, this combo is brutal. The trick is to get them caught in your Null Zone with your Ult. While this is only mandatory if you are trying to down a tank or someone with a lot of magic resist, it's far to pleasing to watch fellow squishies die within 3 seconds.
This is one of the only characters Ive found so far that can take a Rammus from full to almost nothing if not kill him and the true culprit in this regard is the Null Zone. It's damage based on max health makes it equalize the playing field against tanks and tanky dps carries and the wee little squishy mages they love to prey upon. The fact that Nether Grasp Suppresses the target just adds insult to injury when they sit mashing the **** out of their Flash with no success.

(Final Words)

Malhazar is extremely effective but he takes some time to master, I know this because he is incredibly susceptible to ganks and silences during his ult, the true element of being good with him or any squishy little caster is to properly choose your target and be like a scared little rabbit in a field of wolves, panicky and paranoid but never forget... your a scared little rabbit... with a flame thrower.