I can't find a strait answer to this. I read a forum from 2012 but even then there were yes's and no's. I've started playing elise and as a 6th item I was really considering it because I was against a vlad, sion, mundo, and nautilus...all the tank...and if the spiderlings applied the black cleaver, I think that would have been a good choice
Death by Glamour2 votesDont they deal magic damage?
JustSir2 votesDarius's bleed does magic damage too, doesn't it apply stacks? I'm honestly asking. Just started playing this game with the goal of becoming great and am trying to learn what abilities proc what effects
Death by Glamour4 votesDarius's bleed does magic damage too, doesn't it apply stacks? I'm honestly asking. Just started playing this game with the goal of becoming great and am trying to learn what abilities proc what effects
I think darius bleed now does physical after his mini rework.
physical damage will proc the debuff from black cleaver.
JustSir2 votesAH! That makes sense. Just read that the spiderlings only do magic damage...I guess that would be a little bit busted if 5 spiderlings and you cleaved at the same time lol
Void Nargacuga1 votesIt does work with 
Voidlings... And I usually end up getting 40% CDR on him too, and I have him with 
so I heal off the damage dealt by my Voidlings as well.
The key thing with 
is that it says physical damage. Doesn't say YOUR champion (like malzahar) has to deal the physical damage themselves.
Death by Glamour1 votes[{quoted}](name=Bow hunter 16,realm=NA,application-id=3ErqAdtq,discussion-id=2VsJemOh,comment-id=00000000000000000000,timestamp=2015-12-03T19:15:27.707+0000)
It does work with
The key thing with
Do they scale with attack speed ?
Void Nargacuga1 votesSadly no. But they do automatically increase their attack speed once they frenzy. You can look up the info from here its a link to League of Legends Wikia. Just make sure to press the ability details show button for all the juicy info on the Voidlings.
They also are affected by armor penetration. So the precision mastery in cunning is really good since it helps both Malzahar with MR Pen and his Voidlings with Armor Pen.
WarlockLaw1 votesHow do you max cdr on ad Malzahar?
rG Thundrag1 votesHow do you max cdr on ad Malzahar?
Void Nargacuga1 votesI don't build pure AD. I go hybrid semi-tankyish.
My dream build: 
(or 
)
Athene's/Morello's provide 20% CDR getting Cleaver nets another 20% getting you a total of 40% CDR with 2 items.
Void Nargacuga4 votes
bleed damage was changed to physical damage during his rework. Only physical damage can cause to apply its armor cleaving passive.
Sightless661 votesThe answer is no because they apply magic damage. It has to be physical damage for the Cleaver to proc. However, summons that apply physical damage (Malzahar's voidlings) would apply black cleaver.