A tad short, but I like it just as much as your other guides!
Good work yet again.

He's no rammus or leona but malphite does have his place as a anti-carry tank :) looks solid (as rock) love the video, you just need a "in case of AP" section in the guide and you're set :) P.S people take malphite for GRANITE :D

yes, it is in general an anti dps build, but this is malphite, and he is anti dps. As I say in the build, you can grab Mercury's Treads if they are heavy AP, and if they are, grabbing Guardian Angel puts you up at about 190 MR, which is plenty against casters, because that means you are reducing 65% of damage.
As for getting rid of Randuin's Omen, the active is too good to pass up. It can fix a team fight in your favor, and stop people from running. All the slows are incredibly good even against people who do magic damage.
As a tank, you need to do more than soak up damage. You need to ensure your team wins fights.

Good build, but you're lacking mr. Should prolly get merc treads and replace randuins with banshees. This gives you 200/200 which is great for a balanced team. Or you can get mr/lv and still have 200/200. This is more of an anti-ad dps.