Hi. This is a fantastic guide for Malphite, The Shard of the Monolith.
This is a fun guide and is pretty easy to understand your role as Malphite.
Dont be afraid to vote this guide so I know what you guys think and whether I should make another as this is my very first guide.

Pros
-Great Aoe damage from Brutal Strikes, Ground Slam, and Unstoppable Force
-Great disables with a single target slow Seismic Shard, attack speed debuff Ground Slam and aoe knockup Unstoppable Force
-Combination of magic and physical damage makes it hard for opponents to defend against you.
-Still, a great tank with his armor buff and Granite Shield

Cons
-Not as tanky as the general Malphite build everyone goes.
-Once you go in theres no turning back... so you have to time your entrance well. :(
-Yeah no more cons cause he is just that awesome xD

Greater Mark of Attack Speed for the lack of attack speed that malphite has to cope with.
Greater Mark of Desolation and Greater Quintessence of Desolation for the extra boost to his damage output.
Greater Seal of Armor and Greater Glyph of Magic Resist to compensate for the lack of tankiness that this build offers.

Alternative. Trade in your Marks and Quintessence for Greater Mark of Critical Damage and Greater Quintessence of Critical Damage for the extra critical damage that this build not really focuses on but is still viable.

This setup is designed to give the extra damage for Malphite to punish anyone who dares to come too close to him with a boost to his damage output and yet still abit of defence. As this build focuses on offence, 21 points is giving for the ouch factor and 9 in defence just to boost his tankiness.

I choose to put a point in Seismic Shard at lvl 1 just for the slow as you can already tell, Malphite does not have many chasing potential without this skill.
A point in Ground Slam for the aoe slow and damage much needed against any dps.
I choose to max Brutal Strikes first because its a beastly skill and it has soooo much synergy with Tiamat. COME ON MAN. Tiamats? FYI it stacks. So what do you get? Pure awesomeness of 62%+50%+50%+100% damage to anyone around your target and obviously 100% to your original target. And whats this? 40% bonus damage + armor to Malphite? With the ending 277 damage predicted at lvl 18 for this build... 1 GREAT ULT AND YOU GET A PENTA-KILL with your approximately 400 damage with Exilir of Fortitude . Yes I know you guys love pentakills! ;)

Malphite can pretty much go with any summoner spell + Flash with the exception of Promote and Revive
Clarity for the mana problems any malphite has with harassing the opponent in lane. But then again... this build is for dps which means you will not be spamming that much. Not really recommended.
Exhaust best in my opinion as it gives an extra slow and damage debuff, making Malphite a threat in chasing and 1v1 situations.
Ignite for the extra damage to finish anyone off.
Ghost Malphite has not much escape options so this could be it.
Heal not much needed to be said here
Surge extra dps can come in handy ^^
Teleport Malphites crowd controls makes him a great ganker and tele allows him to farm freely.
Cleanse yeah the rock dies rather fast under crowd control with this build
Clairvoyance if you are playing the supportive role earlier on.

The main focus with this build is to give Malphite the maximum farming potential early game for him to scale into a best late game with his auto attacks dealing a ton of damage in an area.
With Tiamats, last hitting is a breeze... wiping creep waves in a matter of 3/4 hits.

Malphite is not only a great tank but also a great pure dps. Be warned though... if timed wrongly, you could be caught between a rock and a hard place xD Have fun summoners!