When should one buy armor/magic resist?

WrÆth·Jun 23, 2016·4 votes·5,184 views

In what situation should one buy armor/magic resist, and when exactly in that game should you get it? Thanks!

20 Comments

xxxDogmanxxxJun 23, 20164 votes

TL DR:

Remember the following rule:

At 50 Armor I should have 1100 HP
At 100 Armor I should have 1500 HP
At 150 Armor I should have 1900 HP

http://i.imgur.com/Wyg0ODz.png

Please have a look to the album:

http://imgur.com/a/3qUe8

I will only present the conclusions here, if you are interested by the calculations of the equilibrium curve, read this document: https://docs.google.com/document/d/1DAuUphj2IAt3QDk_WkfoVqydZ_e7cRCzpFewz9aubU8/edit?usp=sharing

General conclusions:

When you are under the curve, buy health, when you are above the curve, buy armor or magic resist:

http://i.imgur.com/Wyg0ODz.png

The previous conclusion DOES NOT depend on the AD / AP of your opponent. Even if this veigar has 1500 AP, if you have 70 MR and 1000 health you should buy health and not magic resist.

Before the lvl 10 it is more gold efficient to buy health, after the level 10 it is more gold efficient to buy armor or magic resist:

http://i.imgur.com/W2SLkzF.png

Last Whisper and Void Staff move the equilibrium curve. But, against a Void Staff, buying Magic Resist on range champions is still a better option than buying health:

http://i.imgur.com/RdewlmT.png

Rammus gains a huge amount of Armor and MR from his W. Buying health on Rammus is way more efficient early game.

http://i.imgur.com/irAKDrj.png

Cho'Gath (and Renekton in a different way) gains a lot of health from his R. At 6 stacks Cho is widely above the curve. Cho'Gath should NOT buy health. No Rod of Ages. No.

http://i.imgur.com/5ZFOLCW.png

Malphite W bring him 40% bonus armor, and at lvl 18 he is above the curve. So late game armor is very gold efficient on him. But, early game, malphite should buy health before armor (before lvl 12):

http://i.imgur.com/HnRIF0d.png

If you disagree with one of my conclusions, or if you think I made a mistake somewhere, please tell me!

As many of you will point out: This is pure math outside of any real context. In game you won't be able to buy 66 HP for 110 gold. Every item comes with a mix of stat and a passive that must be considered.

About the statement: "health is always more gold efficient early". This does not mean: " build giant belt on Ahri 1st item". Health pots are an excellent way to buy health early for champs that won't need that stat late. Don't forget that after lvl10 armor and mr are better than health. (Rammus still should buy health though)

The results hereby presented are a simplification of a very complex and situational problem. The calculations are based on the linearization of a non-linear problem between Physical and Magic dmg taken independently. In case the enemy team is hybrid, health becomes up to twice as important since it amplifies both Armor and Magic Resistance.

DarfallerJun 23, 20161 votes

Too much math, too much statistics, I THOUGHT HIGH SCHOOL FINISHED FOR ME.

DeathBurstJun 23, 20161 votes

If you disagree with one of my conclusions, or if you think I made a mistake somewhere, please tell me!

Outdated with new LW applying only to Bonus Armor. Also, a similar curve about Black Cleaver would be nice ;)

But that's very interesting already, thanks :)

EDIT: also, not as important, but I'd be interesting in special cases for Leona/Braum.

Re: Cho'Gath, sure you shouldn't buy RoA if you want to maximize your durability, but I still think it's a good item overall for him. Other options with AP+mana are somewhat limited, and even if the HP on RoA are not optimal, it's still better than no defense at all.

MarshbouyJun 23, 20163 votes

... I can't fucking handle people on the boards

You build armor to defend against attack damage you build magic resist to defend against people who deal magic damage.

WrÆthJun 23, 20162 votes

I can't handle people who don't thoroughly read through the article before commenting. I meant when EXACTLY in a game you should buy armor/magic resist, and when you shouldn't but it at all, and it would be more beneficial to continue building AP or AD items.

MarshbouyJun 23, 20163 votes

because it is really obvious. Jesus christ. AP midlaner is fed? Buy MR. ADC Is fed? Buy armor. Who is totally shredding your healthbar? Go into death recap and look at the types of damage you took then build accordingly.

WrÆthJun 23, 20163 votes

Jesus Christ man, please chill the fuck out. Ok, I meant when EXACTLY in a game should you buy those items? Since you obviously have the reading comprehension of a child, an example of an answer would be something like "after your first item" or "__ amount of minutes in", or would it be better to continue building straight AP or AD and skip armor and magic resist completely?

MarshbouyJun 23, 20162 votes

Because that is so incredibly subjective that it's not even worth talking about. I don't have the reading comprehension of a child, im just tired of seeing people on the boards who can't use simple logic. Are you dying fast to X? Build to resist against X. Considering the fact that you are throwing up examples without any champions or champion roles makes in incredibly more annoying for me to read. You won't rush abyssal if you are playing a fucking ADC but you will rush an abyssal if you are playing nautilus top VS ryze or something.

EvilMerodachJun 23, 20164 votes

{quoted}

Because that is so incredibly subjective that it's not even worth talking about. I don't have the reading comprehension of a child, im just tired of seeing people on the boards who can't use simple logic. Are you dying fast to X? Build to resist against X. Considering the fact that you are throwing up examples without any champions or champion roles makes in incredibly more annoying for me to read. You won't rush abyssal if you are playing a fucking ADC but you will rush an abyssal if you are playing nautilus top VS ryze or something.

Missing huge details here- You don't always buy mr vs ap, and always buy armor vs ad. Cause there's this thing called hp, and sometimes hp counters someone better than ar/mr. And there's lifesteal, and items that help you kite item 3153 item 3022 item 3146 item 3025 item 3285 item 3046 item 3116 item 3071 item 3142 Sometimes those are better.

Also, just fk off and don't reply to threads at all if you're just going to call someone stupid for asking a question. Especially when you don't really know the answer yourself. (Cause you're wrong..or binary to the point of uselessness.)

To OP: My rule of thumb- if the enemy can kill you in less than 2 seconds, HP is best. Or item 3102 item 3139 item 3157 if they have a big 1-off combo you can break with the shield/active of those. Zed Veigar Annie etc (your 100-0 champs) If the enemy can't kill you in 2 seconds, def stat most of their damage comes from (ad-ar/ap-mr) If they can kill you when they catch you, but you can work your positioning where they will not catch you, (EG: you're ranged vs Garen Darius DrMundo , etc) look at list of 'kite' items and pick the one that best fits your champ/build.

WrÆthJun 23, 20161 votes

Thank you so much!

BaunjoJun 23, 20161 votes

That's kind of a very broad question, and it won't get you the answer you're looking for. What specific role are we referring to?

bleufromageJun 23, 20161 votes

I can't handle narrow minded people who think that there is always a yes/no question or an exact time or place to build x y or z. There are so many factors in a game that influence what you should be building.

LovelleJun 23, 20161 votes

It depends on who you're playing and what/how they best scale. It also depends on the enemy composition, who's the biggest threat and so on.

In general, if you're playing a tank or bruiser, you'll want at least one armor, Mr, and a health item. The order that you build them in is 100% situational. Squisher champions aren't as dependent on defensive itemization to do their jobs, so for them you pick 1 or 2 items that help them stay alive and keep doing damage.

Tl;dr for tanky champions you want an even Balance of defenses before late game hits. For squishes you'll want at least one defensive item, but don't prioritize it unless you're behind AND it at least provides some dps.

DeathBurstJun 23, 20162 votes

Maybe you should be a little nicer with a level 18 guy that is asking for advice while he's learning the game, don't you think?

BloodyTomponJun 23, 20161 votes

There are a fair few variables at play in that decision. It's easier to see a pro game and say why they picked it in that particular game than it is to outline a kind of large decision tree. It depends on who you are playing, what you intended to do in the game (team fight, split push) and who you are against, both in lane and holistically. It also depends somewhat on if you are ahead or behind.

WrÆthJun 23, 20161 votes

Thank you for an actual answer

DauthauJun 23, 20161 votes

Popularly, if you are behind build damage output while if you're ahead build armor/MR. Unless you're the tank, then build straight outta the gate health and armor/MR.

Very Hard EngageJun 23, 20161 votes

generally you get a health item first, then a resistance + health item. assuming you are building moderately tanky.

DarfallerJun 23, 20161 votes

Always

420 gramsJun 23, 20161 votes

It's situational, but if you're building tank I'd say start cloth armor, then build your health first, then finish the item (probably Randuins) If you're fighting ap go for spirit visage first. If you're support then build your gold income item first, which would probably be face of mountain for tanks supp. If you're ad or ap carry, it's probably better to not buy health or armor and just get more damage. The way it works is it makes your health more x more effective, where x is your armor/Magic resist. So 100 armor and 1000 health would mean it would take 2000 Ad damage to kill you. So building 50 armor and getting 1500 health would give you 2250 effective health (better).