Well Malphite has always been one of the strongest champs in league of legends but due to the lack of mechanics of other champs and basically that none likes to be the tank because we all love THE KILL he fall deep in to the bottom of the popular pick choices this champ not only has great cc but also damage base on armor and a shield for passive what makes him a great top laner but it can also work as good inside your jungle countering most of the annoying new choices like Yasuo jungle and the most hated Master Yi, will even give a great figth to Jax.

Pretty self-explanatory focus on damaging the opponent while tanking as much as possible and supporting the team.

AFTERSHOCK Will raise def. so u can dive team fights and last longer and also will damage the enemy with magic damage based on your max healt

FONT OF LIFE Will heal your teammates after you dive with your R by 5+ 1% again of your max healt

CONFITIONING Huge boost on your defense and resistance allowing you to reach a high defense in an early level countering the insane damage of some of them most popular junglers this will also increase you W and E damage that’s why you are maxim them first.

OVERGROWTH As You can see all this build is based on health and staying alive so this will give you an extra boost of health but you will need to take advantage of the minions on you jungle and help lines in order to max the bonus

THE ULTIMATE HAT You R is your engage so you need it fast and this will help you get it done.

SCORCH Nothing like setting your enemy on fire with a 20 sec. cd ignites.

Pretty clear you are the TANK so no building AP if you want to win the game unless you already know is a won game in this case you can chase the kill like the bronzord you are!.
but no worries you will do more than enough damage with this build to kill any adc or mid in 1 rotation.

SO ONCE AGAIN REMEMBER YOU ARE THE TANK so build correctly.

Pretty clear we are focusing on the skills That benefit the most from the runes like your Brutal Strikes and Ground Slam your Seismic Shard in this build its only you way to slow you target instead of your poke since you will not have enough AP to make that Q count.

Pros
Late game you are as HARD as Alistar but with a better engage
At level 6 your ganks will be really easy thanks to your R
A lot of sustain
Free shield that will save you during low level encounters
Many more...

Cons
Early game is really hard for you if you get invade or set behind
Depends a lot on team communication
If you miss you R u are getting reported!

There are no really pros or cons, with Malphite if u play him right you will get what you look for, a really good tank with a lot of damage able to 1 v 1 basically anything (do not try to 1 v 1 Baron Nashor but if u play him wrong you will be set back and probably get bored and spam surrender all depends on you.