Originally Posted by Cnoized

Actually I'm not making this up, and I'm not QQing. I haven't seen a BC in a game I have played yet, but if you wish to make me prove to you what I'm talking about then here we go.

http://leagueoflegends.wikia.com/wiki/Armor_penetration

Originally Posted by orc72

upvoting. I dont quite get the whole math thing, but I do know when Leona with 200 armor takes as much damage from Jayce as Ahri does with 30 armor (happened to me in game) then somethings wrong.

Originally Posted by Jenna Hazee

BC doesnt counter any tanks because tanks build a lot of health
BC counters bruisers who would build 150-200 armor and be near invincible in season 2

Originally Posted by GreekAsTheGods

Lol... not this ^

If you're only reducing a small fraction of damage then having massive base hp isn't going to work either. The moment crits enter the situation your massive HP will be cut down as fast as your armor was.

If your armor is being ignored to the point that you only reduce incoming physical damage by 30ish% as suggested by OP and you have 3k hp that's fine and dandy until the opponent builds any amount of crits.

I was running around with Statikk Shiv, BC, LW, SotD on Draven and i was dropping 3.5k hp tanks with 200 armor with just the 3 guaranteed crits from SotD. It's pretty ridiculous.

Originally Posted by Ergheis

" Flat armor penetration Edit

The target's armor is treated as being reduced by an amount for purposes of damage calculation, but cannot be reduced below 0. Flat armor penetration stacks additively. "

I just copied this from the webpage that you linked me to prove to me that you were right.

Can you seriously not read

Originally Posted by Jenna Hazee

AD carries should be able to kill tanks if they focus them
if the enemy ad carry is focusing your tank you win the fight for obvious reasons

Let me put this simply for you-
Champs were too tanky in season 2 and that has been adjusted

Originally Posted by Tenmar

So I decided to do a bit of math to really find out how OP AR pen/Reduc is. And while this shouldn't be a shock as to the result, I do have to sadly shame Riot's dev team for how terrible and imbalanced this S3 patch has been that has made this game quite toxic, unfun and unhealthy to play.

But first let's put down the values for the equation so that everyone is on the same page mathematically.

AR Reduction Variables
Black Cleaver(Nami Patch)- 15 Flat AR pen, 30% Ar reduction(four stacks)

Black Cleaver(PBE)- 10 Flat Ar pen(Unique), 25% Ar Reduction(four stacks)

AR Penetration Variables

Marks- 12 Flat Ar Pen
Quints- 7.7 Flat Ar Pen
Marks+Quints=19 Flat Ar pen

Sunder Mastery- 5 flat Ar pen
Weapon Expertise- 8% Ar pen

Last Whisper- 35% Ar Pen

Last Whisper+Weapon Expertise=40% Ar pen

Armor Values

50 Armor=33% Dmg reduction
100 Armor=50% Dmg reduction
150 Armor=60% Dmg reduction
200 Armor=67% Dmg reduction

So with that out of the way let's get on to the equation!

Order of operations

1.Percentage armor reduction=A
2.Flat armor reduction=B
3.Percentage armor penetration=X
4.Flat armor penetration=Y

For the sake of simplicity the armor total will be marked by the variable Z. I would recommend for a base line using the three values of 100, 150 and 200 to reflect a carry, a fighter and a tank.

I will put down the numerical values of the items as well for those who want to see the math for themselves. The non-variable equation will assume that of an AD carry with only Black Cleaver and Last Whisper and the AR pen talents both the % and the 5 flat Ar pen. This will also utilize the Nami Patch.

NOTE: I am not a mathematician and am terrible at writing equations should you or another are an expert at writing equations then please feel free to clean this up and I will give credit where credit is due.

Equation
(Z*A)=ZA(X)= ZAX-Y=Total armor left
[Z*.7(Black Cleaver)]=ZA[.6(Last Whisper+Weapon Expertise)]=ZAX-20 Flat AR pen= Total Armor left

Finally I will post the armor value of 200 to demonstrate why mathematically tanks are no longer able to tank.

200*.7=140*.6=84-20=64 AR(39% Dmg reduction)

A final word, that this equation is utilizing ONE black Cleaver and Zero AR pen Marks/quints. Meaning that if you were to use Ar pen marks,quints and stack a total of 4 BC that would give you a value of 69 AR pen. So a player using all available penetration against that 200 AR tank would end up as this.

84-69=15 Armor=13% Dmg reduction

Thank you very much for your time and I would be greatly appreciated if you could keep this bump to help your fellow player. If you see any potential errors or would like to share your comments or questions please feel free to post.

EDIT: This formula can also be utilize for AP items as well.

Originally Posted by GreekAsTheGods

Do you actually play LoL? ">_> ADC always focuses the front line divers, because if they don't they get crapped on. Doesn't mean you "win the fight". The divers have to be dealt with before moving on and cleaning up the fight.

Champs were NOT too tanky in season 2. It actually took skill to stutter step and kite a tank. Now it does not.... if a tank enters my field of vision when I'm adc I burst it down and move on to next target.

The fact that you can literally just burst down frontlines without having to kite at all and without anyone really having to peel for you is ridiculous. And this is coming from a main ADC.

Also, if you watch competitive play at all then you know how many pentakills ADCs were getting before season 3 patch dropped. There was like 6 just in the finals at IPL5. If tanks were too tanky the ADCs would have been dumped on before they could properly get rid of the front line and wouldn't have been able to move on and clean up the rest of the enemy team.

Tanks are too easy to deal with currently.

Originally Posted by Krampus Claus

I upvoted because, while I disagree with the knee jerk BC QQers (of which there are a lot...), you actually did math and showed your work instead of just posting "OMG I JUST GOT DUNKED BY BLACK CLEAVERS PLX NURFFFFFFFFF!!!!!!!"

I would counter by saying that while BC is a very strong item, and it increases the power of certain champs and strategies, by all means tanks/tanking are/is not useless. There is still room for counterplay, especially because most champs that rely on BC are strong earlygame and rely on snowballing to victory. If you can hold out and have a stronger teamfight, then you can in turn dunk them. Try comps with hard AOE damage and CC like zyra, morg, amumu, and with lots of tankiness, like maokai (AOE damage reduction) or mundo. You'll be able to survive their burst, put out more damage (most BC reliant champs do heavy single target damage), and lock them down. I've been playing a lot since the new patch and, although I've seen my fair share of BC, I've lost to more Eves and Amumus than Pantheons and Talons.