Need a seriously balancing check. These items are built every game in ranked and normals b/c they have a distinct advantage over the other items. If i were a development team, I'd hotfix this asap

Black cleaver needs tons of balancing. It is broken as hell because the % penetration it gives is too much considering the champion damage output was not balanced.

The Liandry's Torment isn't bad though. It helps against tanky DPS

black cleaver has been nerfed into PBE so it should be balanced now.

i really think liandry need to have a look 5% of hp in magic damage is not tought when you have mr but with the changes in pen it take you a lot of health when the ap get sorcerer shoes liandry and void staff, and if you movement is impared it's doubles the effect -.-.
think need a cooldown to be reused the passiva status or not double the effect when the mov is impared i'ts work too well in mushroms of teemo or other strong easy pokes, plus time dot too ;S.

The only thing that BC needs is for the CDR to be unique, just like it is everywhere else, maybe the flat arpen too, but that's not really a big deal. Liandry's is fine as is; I'm pretty sure the only champs who can get the full 10% off of it are Anivia, after she gets her ult, and Karthus. Of course, that's assuming you have 0 MR.

There could be others, but what's required is 1) a 3-second slow, stun, or snare (or perfect chain thereof), 2) a single-target, non-DoT, magic-dealing spell, 3) the removal of all your MR (e.g. Abyssal Fidd is nearby when you have 0 bonus MR), and 4) your hp regen is reduced to 0. Then, and only then, will Liandry's deal a full 10% of your health over 3 seconds. If any one of those conditions is not met, you're looking at as much as an 80% reduction off of that.

For example, if there's no shred around (not pen mind you; has to be shred 'cause items don't use pen), and/or you have even one of the +50 MR items (or have it naturally), you've cut the damage by 40%, which means if all of parts 1, 2,& 4 are in place, you'll only take 6% of your hp as damage from Liandry's. If you have decent regen, and most champs naturally have on the order of 15-20 hp/5 w/o masteries or runes, that by itself will offset 10-12 hp lost, which is 1% of most squishy champions' hp.

Coupled with MR, that puts Liandry's down to only 5% of your health. Now, if you are not slowed/snared/stunned for the full 3 seconds, every second you're not slowed only deals half as much damage; with a little MR & regen (e.g. one Spirit Visage) you can take as little as 2-3% of your health as damage from Liandry's. Finally, if the final spell that hits you is a multi-target, aoe, or dot, that will cut Liandry's down by half again, for a base of only 2.5%, further reduced by MR and regen to as little as one half of a percent (0.5%) of your health as damage. Get a Warmogs + SV and your damage could be effectively 0 (because Warmogs gives you back 1.5% of your health over the same time period, increased to 1.8% per 5 or 1% per 3 which nets you positive gain).

So, quit whining about Liandry's, it's hard-countered by Spirit Visage: buy one, get tenacity or don't get stunned, and don't worry unless your opponent is Karth, Aniv, Vlad, Kass, or Brand.