Talk:The Black Cleaver/@comment-6015339-20130222045401

Tested a few things from the comments below:

Tiamat/Hydra (passive and active) will apply Black Cleaver stacks to surrounding units. A direct auto attack will apply only one stack.

Abilities with an attack component (Talon's Q) apply two stacks -- one for the auto attack, one for the ability damage. Didn't test Iceborn Gauntlet -- does it apply one for the auto attack plus one for its AOE damage?

Physical damage over time (Talon's Q) applies Black Cleaver on every tick. (Talon's Q applies three stacks instantly -- one for the auto attack, one for ability damage, one for the first instantaneous tick.)

Malzahar's voidlings will apply Black Cleaver stacks (I expect other physical damage pets apply stacks as well).