
Gentleman Gustaf here to re-analyze Health and Resistances, now that Pre-Season 3 has started to settle down. A few things have changed:
- Health's cost is down (5%)
- Resistances' costs are up (15%)
- %Pen stacks with Flat Pen without wasting any
- %Armor Reduction is readily available
How has this affected the balance you should maintain between health and resistances?
Before I dig deep into the numbers, I want to point a number of things out: Resistances don't just scale your burst 100-0 tankiness: they also provide multiplicative benefits to lifesteal, shields, heals, and regen. So if you are a champion who has such abilities, you should bias yourself more towards resistances. The way I would do so would be as follows: calculate how much you expect to lifesteal/shield/heal/regen during an 8-10 second interval, and add that amount to your health.
Calculating Tankiness
With that out of the way, let's jump right in. First, let's recap the important equations.
We have the equations for calculating Effective Health vs Physical Damage (PEHP) and Effective Health vs Magical Damage (MEHP), as well as their average (EHP)

From there, we can calculate the increase each point of Health or Armor (sub for MR as needed) gives you.

Let's say that the enemy team has nothing but physical damage. Do we want nothing but Armor? Turns out, no, for a pretty intuitive reason. The value of each point of Health, as shown above, is (1+Armor/100), and the value of each point of Armor is Health/100. So given any combination of Health and Armor, if we stack armor infinitely, the value of Health will go up and up (as your amount of Armor goes up and up). Eventually, Health will just be worth more. By factoring in the relative costs of Health and Armor, we can calculate how much of each we want:

So if you're against an entirely Physical team, you want a lot of armor, but not nothing but Armor. A good sweet spot is about 3000 Health and 300 Armor. But wait! Aren't they going to at least going to have 8 %Pen from masteries? That should mean you get less armor, right? Yes. However, how much may come as a surprise. Even though I knew what numbers to expect, having done these calculations before, I feel a bit weird seeing them. The amount less is a flat amount. That is, while %Pen may go through a percentage of your armor, you shouldn't buy a percentage less. This is because there are two factors at work. The first, the %Pen of the Armor you ALREADY have, decreases the value of health. The second, the % Pen on Armor you would buy in the future, decreases the value of Armor. These two cancel out, leaving you with a flat amount. How much? 8.7 Armor, or (1/(1-.08)-1). Now, let's add LW into the mix, for another 35% Pen! The results are the same as above, you should get (1/((1-.08)*(1-.35))-1) less armor, or 67. Add on BC's % Pen, and you're up to 139! Here the graphs are together:

But Gentleman Gustaf, what about the flat pen on Black Cleaver?
Up until now, I've just been looking at % Pen. But let's account for the 10 Pen from Cleaver, and the 5 from masteries. If there were no %Pen involved, the answer would be easy: Get 15 Armor to make up for the 15 Pen and get back on the optimizing line. However, since % Pen is involved, things get a little bit more complicated. Why? Because 15 Armor isn't worth 15 Armor anymore. To actually get 15 Armor, you need 15/.4186, or 15/(1-%Pen). In this case, that's 35.83 Armor.
And this is exactly the problem with Black Cleaver, conceptually. Brutalizer says 'get 10 Armor to make up for this Pen!'. Then you upgrade it to Black Cleaver, and get %Pen, which says 'get 4 more Armor to make up for the Flat Pen being harder to make up!', but follows it up with 'also, get 43 less armor, because your armor is worthless!'
More on the past of Black Cleaver, if you're interested:
This is why making the Flat Pen unique was such a huge deal in nerfing Black Cleaver. Imagine 4 Black Cleavers, saying 'GET 60 ARMOR!'. That 60 Armor becomes 85 on account of the % Pen, but now you're stacking tons of armor in the face of a huge amount of % Pen, just to make up for the flat pen. With 2 BCs, LW and the 8% from masteries, you ended up needing 85 Armor JUST to make up for the Flat Pen the Black Cleavers and masteries gave, and that's not even accounting for the base Armor you'd want. Let's say you had 2250 health, and wanted to buy some Health. How much armor would you need to start switching over to Armor? 157. That meant for squishier champions, they spent their first item of tankiness just to get back to the break-even point for health/armor. For every 250 health you picked up, you should also have picked up about 35 armor. It's pretty easy to see how this would start to snowball out of control. Basically, you had to dump 2 defensive items into armor for every one into health.
On top of that, if the enemy team was all AD, they benefited immensely from this (all penetrating your armor). But worse, if one was magic damage, you still weren't particularly safe stacking health.
Of course, most games, the team probably won't be all physical or all magical damage, and you'll end up having to weight your choices accordingly.
So what should you do if you are faced with an even split?

The close observer may note that this graph is the same as just Armor, but with 100 points fewer spent on resistances. So if you have 3k health against only physical damage, you want about 300 Armor. But if you have 3k health against split damage, you want about 200 resistances (summed). From there, it's a matter of figuring how much of their damage is physical, and how much is magical, and finding an appropriate middle ground between a perfect Resistances split and a 100% Armor page.
TL;DR
Don't get resistances until you have about 1500 HP.
Then get 0-100 points in the resistance of your choice, based on physical/magical balance of their team; 100 being all one type, 0 being an even split.
Then get 1 point in the resistance of your choice for every 75 health you get
Flat Pen - Get extra armor equal to their flat pen divided by the complement of their %Pen.
%Pen - Get less armor equal to 100/(%Pen)-100
Obviously, items don't come in continuous quantities, so just aim to be somewhere near this rubric.
Also, different champions are different, so if you have shields or heals, get some more resistances, and if they have % Health damage, get more resistances.
For more of my work:
-- Find old posts @ the RoG forums and new posts every Wednesday (3 PM) and Sunday (9 AM).
-- Feel free to find me in the "A DIFFerent View" chatroom on the NA server.
-- Contact me at GentlemanGustaf@ReignofGaming.net
-- Follow me on Facebook and Youtube for updates on all of my new articles, videos, and streaming.
Gentleman of the Day

-
View User Profile
-
Send Message
Posted 1/31/2013 6:07:58 PMI really like this article. It's the kind of thing I've been trying to do for a while, unsuccessfully because I insist on using game examples rather than flat lines.
I would be interested in seeing further graphs for different incoming damage splits though. Not a fan of using the 50/50 split as your EHP, since it's rare these days for 50% of incoming damage to ever be magical. A set of graphs for 20/80, 40/60, 60/40 and 80/20 would be nice to see :)
My definition of ELO Hell:-
"Any point at which ego is greater than ELO."
-
View User Profile
-
Send Message
Posted 1/31/2013 12:30:54 PMWill try your recommendations, it seems to me you did the right math
-
View User Profile
-
Send Message
Posted 1/31/2013 10:33:13 AMI feel like you didn't finish. Look at the differences between the original armor/health graph and the mega-penetration version. It drops 180ish points!
But your conclusions are based on the Combined armor/MR/health chart, which ASSUMES NO PENETRATION! There IS magic penetration too, right? And armor pen still exists.
So technically you would need to make a penetration chart for MR/health like you did with armor. Then take the average case of both, combine them to make a Combined armor/MR with average-case of penetration vs Health chart.
Clearly, it would drop the line on the combined chart even further than what you already have due to the penetrations. If resists are crap until 1500 health WITHOUT PEN, just imagine the chart AFTER penetration!
Remember that you ALREADY GET some armor/MR for free... usually about 100 armor and 75 MR for bruisers from runes/masteries and natural progression. So factoring in that, you wouldnt actually even look at armor/MR until 2k health...in the NON-PENETRATION version.
I'd be willing to bet that in the penetration version of the combined chart if created, it would show that armor/MR are basically worthless until 3k health.
-
View User Profile
-
Send Message
Posted 1/31/2013 1:54:08 PMExcept people don't typically get % MPen (minus the 8%, and flat Pen actually prompts MORE Resistances, not less)
-
View User Profile
-
Send Message
Posted 1/31/2013 9:12:03 AMThis is pretty useful. Thank you mate.
-
View User Profile
-
Send Message
Posted 1/31/2013 7:23:09 AMIsn't that analyze a bit early? Next patch HP will get nerfed (Giants belt, Warmogs, Sunfire, Locket, ...).Most HP + Armor items will stay as they are (Randuins) cause most late game armor will be a bit cheaper (Frozen Heart getting cheaper).
So in one week you need to re-analyze the revisit.
-
View User Profile
-
Send Message
Posted 1/31/2013 8:36:03 PMThat's the beauty of it though. Once GG has gone to the effort of tabulating this sort of data, it probably wont be too much work to just input the changes and, voila, revised graphs etc. Unless something rather fundamental changes.
-
View User Profile
-
Send Message
Posted 1/31/2013 6:12:34 AMIsn't the PEHP formula as following:
PEHP=Health*(100+Armor/100),
instead of
PEHP=Health*(1+Armor/100),
since the Damage Formula for physical damage goes as following:
Actual Damage=Damage*100/(100+Armor),
meaning that if someone deals 100 damage and you have 50 armor you take
100*100/(100+50)
10 000/150=66.667
damage. If you have 100 Armor you take 50% reduced physical damage (Fact, look it up), and this can we prove with the Damage Formula:
Damage*100/(100+100)
Damage*100/200
Damage*0.5
So, back to PEHP,
You have 1000 HP and 100 armor. how much PEHP do you have?
1000*(1+100/100)
1000*1.01=1001.01
or
1000*(100+100/100)
1000*2=2000
We have 2 possibilities, do you have 1001.01 PEHP or 2000 PEHP? The obvious answer is 2000 PEHP.
I don't really see where I'm wrong, but since Gustaf is a lot smarter than me, I guess I have missed something. May I ask where?
-
View User Profile
-
Send Message
Posted 1/31/2013 6:27:53 AM1000*(1+100/100) = 1000*(1+1) = 2000
Your way:
1000*(100+100/100) = 1000*(101) = 101000.
EDIT: Ah, I see where you went wrong:
You thought: HP*((1+Armor)/100), while it is actually HP*(1+(Armor/100))
http://www.reignofgaming.net/forums/strategy/runes-and-mastery-discussion/29950-mastery-theorycrafting-fury-aspd-vs-sorcery-cdr#c1
http://www.reignofgaming.net/forums/strategy/runes-and-mastery-discussion/30216-mastery-theorycrafting-ehp-and-the-defensive-tree
http://www.reignofgaming.net/forums/strategy/champions-and-gameplay/30253-why-ap-carries-should-rush-haunting-guise#c8
-
View User Profile
-
Send Message
Posted 1/31/2013 8:13:46 AMOh... right. This is a bit awkward... That was pretty obvious if you know the order of operations, which I actually (normally) do, but I guess I just went full retard.
Thanks for straightening things up though, you were not only right about how it actually is, but also about how I thought.
-
View User Profile
-
Send Message
Posted 1/31/2013 1:55:41 PMYeah, I was thinking the same thing reading it :P Thank you to the above commenter for clearing that up.
-
View User Profile
-
Send Message
Posted 1/31/2013 3:59:17 AMTheory aside. It would be interesting to see some real data points for in game items on these charts!
-
View User Profile
-
Send Message
Posted 1/31/2013 12:46:10 PMyou know theory crafting? that kindda what ADV is known for. Let the word roll over your tongue THEEEEEEORYYYYYYY crafting, yes THEORY!
-
View User Profile
-
Send Message
Posted 1/31/2013 8:33:11 PMInputting some numbers for actual items in the game would still be a theoretical treatment... No less 'theory crafted' than obtaining the direct relationship shown in this post. For example, you could look at every item as a first buy, second buy etc. and show how close to the ideal relationship certain combinations of items were. Does the info in this post give us the capability to do that ourselves? Yes. But, I for one would find a simple infographic using actual in game items much more informative. That's all I was saying really.
-
View User Profile
-
Send Message
Posted 2/4/2013 4:12:12 PMThat and