An intentional exception to this is Senna'sAbsolution's innate bonus damage on-hit; she generates 2 stacks of Carve with every attack to offset her low attack speed.
Note that the excluded on-hits will sometimes not apply the armor shred. If they're triggered by Guinsoo's Rageblade they will however always apply it. Runaan's Hurricane will also apply the shred to the main target since it deals them 0 physical damage on-hit.
The very first instance of physical damage does not get the benefit of the armor reduction. The physical damage dealt is calculated first, and the debuff is applied after. This means the full benefit of the reduction is seen on the seventh hit, after all six stacks have been applied.
Based on the effect, multiple instances of physical damage applied at the same will only apply one stack. (bug)
Black Cleaver is usually used on juggernauts (Illaoi, Darius, Garen) because they can easily apply stacks and survive long enough to benefit from the penetration.
Armor reduction and penetration effects stack, allowing an attacking character to benefit simultaneously from Black Cleaver's shred, penetration runes, other items such as Last Whisper, and champion abilities that circumvent armor.
The icons to the right feature the old indicator used to represent the target's armor was reduced.
In the now-removed official League of Legends forums, the first icon of Black Cleaver was used to represent the "Item Discussion" section.
Black Cleaver and Obsidian Cleaver are among a number of items that had the word "The" removed from their names in patch V9.19. They were previously known as The Black Cleaver and The Obsidan Cleaver respectively.
Bug Fix:Titanic Hydra's Cleave and certain other on-hit effects from items and Champion passives no longer apply an additional stack of Carve on basic attacks if Black Cleaver's effect was acquired later (in a higher buff slot) than the on-hit effect.
New Unique Passive - Rage: Dealing physical damage to a champion grants 5 bonus movement speed per stack of Carve on them for 2 seconds, up to 30.
Removed Unique Passive - Butcher: Basic attacks on-hit and abilities that deal physical damage against fully Shredded enemies deal bonus physical damage equal to 5% of their missing health. This is reduced to 2% of their missing health for damage over time effects, which may only deal the bonus damage every 0.5 seconds.
Unique Passive - Carve: Dealing physical damage to an enemy champion reduces their armor by 4% for 6 seconds, stacking up to 6 times for a maximum of 24%. Enemies with 6 stacks are Shredded.
Unique Passive - Butcher: Basic attacks (on-hit) and damaging abilities against fully Shredded enemies deal bonus physical damage equal to 5% of their missing health, reduced to 2% of their missing health for damage over time effects (0.5 second cooldown).
Unique Passive: Dealing physical damage to an enemy champion Cleaves them, reducing their armor by 4% for 6 seconds, stacking up to 6 times for a maximum of 24%.
Unique Passive - Rage: Dealing physical damage grants ( 20 / 10) movement speed for 2 seconds. Assists on Cleaved enemy champions or kills on any unit grant ( 60 / 30) movement speed for 2 seconds instead.
Revised Passive: Dealing physical damage to an enemy champion Cleaves them, reducing their armor by 5% for 6 seconds, stacking up to 6 times.
The passive is now unique.
New Unique Passive:Rage: Dealing physical damage grants 20 movement speed for 2 seconds. Assists on Cleaved enemy champions or kills on any unit grant 60 movement speed for 2 seconds instead. This movement speed is halved for ranged champions.