Secret Lesson 64

Armor and Shields: Armor Class, Training, Strength Requirements, Stealth, and Donning or Doffing Armor

In the previous three lessons, we mastered:

WEAPONS

WEAPON PROPERTIES

and:

WEAPON MASTERY

Now we move from:

OFFENSE

to:

DEFENSE

One of the most important defensive statistics in 5E is:

ARMOR CLASS

usually abbreviated:

AC

Armor Class answers a fundamental question:

HOW DIFFICULT ARE YOU TO HIT?

When an enemy makes an Attack Roll against you, that attack normally succeeds if its total:

EQUALS OR EXCEEDS YOUR AC

Armor can replace your normal AC calculation with a new one.

A Shield can increase it further.

But armor also introduces several additional rules:

ARMOR TRAINING

DEXTERITY MODIFIERS

STRENGTH REQUIREMENTS

STEALTH DISADVANTAGE

DONNING AND DOFFING TIMES

and:

EQUIPMENT LIMITS

Understanding armor therefore means understanding much more than:

"BIGGER NUMBER = BETTER"

PART ONE — THE THREE ARMOR CATEGORIES

Every suit of armor in the main SRD Armor table belongs to one of three categories:

LIGHT ARMOR

MEDIUM ARMOR

or:

HEAVY ARMOR

 

These categories determine two major things:

HOW THE ARMOR CALCULATES AC

and:

HOW LONG IT TAKES TO DON OR DOFF

the armor.

PART TWO — COMPLETE ARMOR TABLE

Armor Armor Class Strength Stealth Weight Cost
Light Armor
Padded Armor 11 + Dex modifier — Disadvantage 8 lb. 5 GP
Leather Armor 11 + Dex modifier — — 10 lb. 10 GP
Studded Leather Armor 12 + Dex modifier — — 13 lb. 45 GP
Medium Armor
Hide Armor 12 + Dex modifier (max 2) — — 12 lb. 10 GP
Chain Shirt 13 + Dex modifier (max 2) — — 20 lb. 50 GP
Scale Mail 14 + Dex modifier (max 2) — Disadvantage 45 lb. 50 GP
Breastplate 14 + Dex modifier (max 2) — — 20 lb. 400 GP
Half Plate Armor 15 + Dex modifier (max 2) — Disadvantage 40 lb. 750 GP
Heavy Armor
Ring Mail 14 — Disadvantage 40 lb. 30 GP
Chain Mail 16 Str 13 Disadvantage 55 lb. 75 GP
Splint Armor 17 Str 15 Disadvantage 60 lb. 200 GP
Plate Armor 18 Str 15 Disadvantage 65 lb. 1,500 GP
Shield +2 — — 6 lb. 10 GP

These are the complete nonmagical armor and Shield entries in the main SRD table.

PART THREE — NORMAL ARMOR CLASS

Without another base AC calculation, your normal base AC is:

10 + DEXTERITY MODIFIER

The Rules Glossary also establishes an important principle:

If a rule gives you another:

BASE AC CALCULATION

you choose which calculation to use.

You cannot combine:

MULTIPLE BASE AC CALCULATIONS

together.

EXAMPLE — NO ARMOR

Dexterity:

16

Dexterity modifier:

+3

Base AC:

10 + 3 =

AC 13

PART FOUR — ARMOR GIVES A DIFFERENT BASE AC

When you wear armor, the Armor table tells you:

YOUR BASE AC CALCULATION

For example:

Leather Armor:

11 + DEXTERITY MODIFIER

Chain Mail:

AC 16

These are different ways of calculating:

BASE AC

 

IMPORTANT

You don't normally calculate:

10 + DEX

and then add:

THE ARMOR'S AC

That would be incorrect.

The armor gives you:

A NEW BASE AC CALCULATION

WRONG EXAMPLE

Leather Armor:

11 + DEX

Dexterity modifier:

+3

Don't calculate:

10 + 3 + 11 =

24

That isn't the rule.

CORRECT

Leather Armor:

11 + 3 =

AC 14

PART FIVE — LIGHT ARMOR

Light Armor uses:

YOUR FULL DEXTERITY MODIFIER

The three Light Armors are:

PADDED ARMOR

LEATHER ARMOR

and:

STUDDED LEATHER ARMOR

LIGHT ARMOR AC FORMULA

Padded:

11 + DEX MODIFIER

Leather:

11 + DEX MODIFIER

Studded Leather:

12 + DEX MODIFIER

 

PART SIX — LIGHT ARMOR AND HIGH DEXTERITY

Because Light Armor has no listed maximum on the Dexterity modifier:

YOUR FULL DEX MODIFIER APPLIES

EXAMPLE — DEXTERITY 18

Dexterity modifier:

+4

Leather Armor:

11 + 4 =

AC 15

Studded Leather:

12 + 4 =

AC 16

DEXTERITY 20

Modifier:

+5

Studded Leather:

12 + 5 =

AC 17

PART SEVEN — LIGHT ARMOR AND LOW DEXTERITY

A negative Dexterity modifier also affects the calculation.

EXAMPLE

Dexterity:

8

Modifier:

−1

Leather Armor:

11 − 1 =

AC 10

Studded Leather:

12 − 1 =

AC 11

The armor doesn't say:

MINIMUM DEX MODIFIER 0

So apply the actual modifier.

PART EIGHT — PADDED ARMOR

Padded Armor:

Base AC:

11 + DEX MODIFIER

Weight:

8 LB.

Cost:

5 GP

Stealth:

DISADVANTAGE

EXAMPLE

Dexterity:

16

Modifier:

+3

Padded Armor:

11 + 3 =

AC 14

But while wearing it:

DEXTERITY (STEALTH) CHECKS HAVE DISADVANTAGE

PART NINE — LEATHER ARMOR

Leather Armor:

11 + DEX MODIFIER

Weight:

10 LB.

Cost:

10 GP

Stealth:

NO DISADVANTAGE LISTED

EXAMPLE

Dexterity:

16

Modifier:

+3

AC:

11 + 3 =

14

PART TEN — STUDDED LEATHER ARMOR

Studded Leather:

12 + DEX MODIFIER

Weight:

13 LB.

Cost:

45 GP

No Stealth Disadvantage is listed.

EXAMPLE

Dexterity:

18

Modifier:

+4

AC:

12 + 4 =

AC 16

PART ELEVEN — LIGHT ARMOR COMPARISON

With Dexterity modifier:

+3

Padded:

11 + 3 =

14

Leather:

11 + 3 =

14

Studded Leather:

12 + 3 =

15

But Padded additionally imposes:

STEALTH DISADVANTAGE

This demonstrates why armor selection isn't only about:

AC

You should also examine:

COST

WEIGHT

and:

STEALTH

PART TWELVE — MEDIUM ARMOR

Medium Armor uses Dexterity differently.

Its formulas are:

BASE NUMBER + DEXTERITY MODIFIER, MAXIMUM +2

The five Medium Armors are:

HIDE ARMOR

CHAIN SHIRT

SCALE MAIL

BREASTPLATE

and:

HALF PLATE ARMOR

 

PART THIRTEEN — WHAT "DEX MODIFIER MAX 2" MEANS

Suppose your Dexterity modifier is:

+2

You add:

+2

Suppose it is:

+4

You still add only:

+2

Suppose it is:

+5

Still:

+2

The armor caps:

THE POSITIVE DEXTERITY CONTRIBUTION

at +2.

PART FOURTEEN — MEDIUM ARMOR WITH NEGATIVE DEXTERITY

The table says:

DEX MODIFIER (MAX 2)

It doesn't establish a minimum of:

0

So a negative Dexterity modifier still applies.

EXAMPLE

Dexterity:

8

Modifier:

−1

Half Plate:

15 − 1 =

AC 14

PART FIFTEEN — HIDE ARMOR

Hide Armor:

12 + DEX MODIFIER, MAX +2

Weight:

12 LB.

Cost:

10 GP

No Stealth Disadvantage listed.

DEX +0

AC:

12 + 0 =

12

DEX +2

AC:

12 + 2 =

14

DEX +4

Maximum allowed contribution:

+2

AC:

14

not:

16

PART SIXTEEN — CHAIN SHIRT

Chain Shirt:

13 + DEX MODIFIER, MAX +2

Weight:

20 LB.

Cost:

50 GP

No Stealth Disadvantage listed.

EXAMPLE

Dexterity modifier:

+2

AC:

13 + 2 =

15

DEX +4

Still:

13 + 2 =

AC 15

PART SEVENTEEN — SCALE MAIL

Scale Mail:

14 + DEX MODIFIER, MAX +2

Weight:

45 LB.

Cost:

50 GP

Stealth:

DISADVANTAGE

EXAMPLE

Dexterity modifier:

+2

AC:

14 + 2 =

16

But:

DEXTERITY (STEALTH) CHECKS HAVE DISADVANTAGE

PART EIGHTEEN — BREASTPLATE

Breastplate:

14 + DEX MODIFIER, MAX +2

Weight:

20 LB.

Cost:

400 GP

No Stealth Disadvantage listed.

EXAMPLE

Dexterity modifier:

+2

AC:

16

IMPORTANT COMPARISON

Scale Mail and Breastplate can both reach:

AC 16

with Dex +2.

But:

Scale Mail:

50 GP

and:

STEALTH DISADVANTAGE

Breastplate:

400 GP

and:

NO STEALTH DISADVANTAGE LISTED

The more expensive armor therefore doesn't merely change:

AC

It can also change:

OTHER CHARACTER CAPABILITIES

PART NINETEEN — HALF PLATE ARMOR

Half Plate:

15 + DEX MODIFIER, MAX +2

Weight:

40 LB.

Cost:

750 GP

Stealth:

DISADVANTAGE

DEX +0

AC:

15

DEX +1

AC:

16

DEX +2

AC:

17

DEX +4

Still:

AC 17

because the Dexterity contribution is capped at:

+2

PART TWENTY — MAXIMUM NONMAGICAL MEDIUM-ARMOR AC FROM THE TABLE

With Half Plate and Dexterity +2 or higher:

15 + 2 =

AC 17

before considering something separate such as:

A SHIELD

WITH SHIELD

If the character has appropriate Shield training:

17 + 2 =

AC 19

This combines:

THE ARMOR'S BASE AC

with:

THE SHIELD'S +2 BONUS

PART TWENTY-ONE — MEDIUM ARMOR COMPARISON AT DEX +2

Medium Armor AC Stealth
Hide 14 Normal
Chain Shirt 15 Normal
Scale Mail 16 Disadvantage
Breastplate 16 Normal
Half Plate 17 Disadvantage

This illustrates the trade-off between:

DEFENSE

STEALTH

COST

and:

WEIGHT

PART TWENTY-TWO — HEAVY ARMOR

Heavy Armor works differently from both:

LIGHT

and:

MEDIUM

The Heavy Armor table gives:

FIXED AC VALUES

You don't add your Dexterity modifier.

The four Heavy Armors are:

RING MAIL

CHAIN MAIL

SPLINT ARMOR

and:

PLATE ARMOR

 

PART TWENTY-THREE — DEXTERITY DOES NOT MODIFY HEAVY ARMOR AC

Ring Mail:

AC 14

Chain Mail:

AC 16

Splint:

AC 17

Plate:

AC 18

These are the listed AC values.

EXAMPLE — DEXTERITY 20

Plate Armor:

AC 18

You don't calculate:

18 + 5 =

23

The armor says:

AC 18

EXAMPLE — DEXTERITY 8

Modifier:

−1

Plate still gives:

AC 18

You don't subtract Dexterity either.

PART TWENTY-FOUR — RING MAIL

Ring Mail:

AC 14

Strength requirement:

NONE

Stealth:

DISADVANTAGE

Weight:

40 LB.

Cost:

30 GP

IMPORTANT

Ring Mail is Heavy Armor but doesn't list:

A STRENGTH REQUIREMENT

So it doesn't reduce Speed through the armor Strength rule merely because it belongs to:

HEAVY ARMOR

PART TWENTY-FIVE — CHAIN MAIL

Chain Mail:

AC 16

Strength:

13

Stealth:

DISADVANTAGE

Weight:

55 LB.

Cost:

75 GP

PART TWENTY-SIX — SPLINT ARMOR

Splint Armor:

AC 17

Strength:

15

Stealth:

DISADVANTAGE

Weight:

60 LB.

Cost:

200 GP

PART TWENTY-SEVEN — PLATE ARMOR

Plate Armor:

AC 18

Strength:

15

Stealth:

DISADVANTAGE

Weight:

65 LB.

Cost:

1,500 GP

Among the ordinary armor in the main table, Plate provides the highest listed base AC:

18

PART TWENTY-EIGHT — ALL HEAVY ARMOR IMPOSES STEALTH DISADVANTAGE

Every Heavy Armor entry in the SRD table has:

DISADVANTAGE

in the Stealth column.

That includes:

RING MAIL

CHAIN MAIL

SPLINT

and:

PLATE

 

PART TWENTY-NINE — WHAT THE STEALTH COLUMN MEANS

If the table shows:

DISADVANTAGE

in the Stealth column, the wearer has:

DISADVANTAGE ON DEXTERITY (STEALTH) CHECKS

 

IMPORTANT

This doesn't mean:

DISADVANTAGE ON EVERY DEXTERITY CHECK

because of the Stealth column.

It specifically applies to:

DEXTERITY (STEALTH)

EXAMPLE

Plate wearer makes:

DEXTERITY (STEALTH)

Roll:

TWO D20S

Use:

THE LOWER RESULT

BUT

A Dexterity (Acrobatics) check doesn't receive Disadvantage merely because Plate has:

STEALTH DISADVANTAGE

Another rule would be needed for that.

PART THIRTY — ARMORS WITH STEALTH DISADVANTAGE

The main Armor table applies it to:

PADDED ARMOR

SCALE MAIL

HALF PLATE ARMOR

RING MAIL

CHAIN MAIL

SPLINT ARMOR

PLATE ARMOR

ARMORS WITHOUT IT LISTED

LEATHER

STUDDED LEATHER

HIDE

CHAIN SHIRT

BREASTPLATE

PART THIRTY-ONE — STRENGTH REQUIREMENTS

Some Heavy Armor has a value in:

THE STRENGTH COLUMN

The rule is:

If your Strength score is lower than:

THE LISTED SCORE

your Speed is reduced by:

10 FEET

 

IMPORTANT

This is not a requirement to:

WEAR THE ARMOR

The rule doesn't say:

"YOU CANNOT WEAR IT"

It says insufficient Strength causes:

−10 FEET SPEED

PART THIRTY-TWO — CHAIN MAIL STRENGTH

Chain Mail:

STRENGTH 13

Character Strength:

12

Speed:

30 FEET

Reduction:

30 − 10 =

SPEED 20 FEET

STRENGTH 13

You meet the listed score.

Speed remains:

30 FEET

assuming no other rule modifies it.

PART THIRTY-THREE — SPLINT AND PLATE

Splint:

STRENGTH 15

Plate:

STRENGTH 15

EXAMPLE

Strength:

14

Base Speed:

30 FEET

Wearing Plate:

SPEED 20 FEET

STRENGTH 15

Speed:

30 FEET

because the requirement is satisfied.

PART THIRTY-FOUR — STRENGTH REQUIREMENTS DO NOT CHANGE AC

Suppose you have:

Strength:

10

and wear:

CHAIN MAIL

Chain Mail still gives:

AC 16

The insufficient Strength causes:

SPEED −10 FEET

It doesn't say:

AC IS REDUCED

PART THIRTY-FIVE — STRENGTH REQUIREMENTS DO NOT AUTOMATICALLY GIVE DISADVANTAGE

The armor's Strength rule only says:

SPEED −10 FEET

It doesn't say insufficient Strength gives:

DISADVANTAGE ON ATTACKS

DISADVANTAGE ON SAVES

or:

DISADVANTAGE ON CHECKS

Those penalties could come from another rule, but not merely from failing:

THE ARMOR'S STRENGTH SCORE

PART THIRTY-SIX — ARMOR TRAINING

Now we reach one of the most important armor rules.

Anyone can:

DON ARMOR

or:

HOLD A SHIELD

But only characters with appropriate:

ARMOR TRAINING

can use them effectively.

A character's:

CLASS

and other:

FEATURES

determine which armor categories they have training with.

PART THIRTY-SEVEN — ARMOR TRAINING IS CATEGORY-SPECIFIC

Training can cover:

LIGHT ARMOR

MEDIUM ARMOR

HEAVY ARMOR

and:

SHIELDS

These aren't automatically one package.

EXAMPLE

A character might have training with:

LIGHT ARMOR

but not:

MEDIUM ARMOR

Wearing Medium Armor would therefore invoke:

THE UNTRAINED-ARMOR RULE

PART THIRTY-EIGHT — WEARING ARMOR WITHOUT TRAINING

If you wear:

LIGHT

MEDIUM

or:

HEAVY ARMOR

and lack training with that armor category, two major penalties apply.

First:

DISADVANTAGE

on any:

D20 TEST

that involves:

STRENGTH

or:

DEXTERITY

Second:

YOU CAN'T CAST SPELLS

 

PART THIRTY-NINE — WHAT "ANY D20 TEST" MEANS

Remember:

D20 TEST

is the game's umbrella term for:

ABILITY CHECKS

SAVING THROWS

and:

ATTACK ROLLS

So if an untrained armor wearer makes one of those tests and it involves:

STRENGTH

or:

DEXTERITY

the roll has:

DISADVANTAGE

EXAMPLE — STRENGTH ATTACK

Character lacks Heavy Armor training.

Wears:

PLATE

Makes a Strength-based Longsword Attack Roll.

Because the D20 Test involves:

STRENGTH

Attack Roll:

DISADVANTAGE

PART FORTY — DEXTERITY ATTACK

Same untrained armor wearer fires a:

LONGBOW

using Dexterity.

The Attack Roll involves:

DEXTERITY

Therefore:

DISADVANTAGE

PART FORTY-ONE — STRENGTH CHECK

Character attempts:

STRENGTH (ATHLETICS)

while wearing armor they lack training with.

Result:

DISADVANTAGE

PART FORTY-TWO — DEXTERITY SAVING THROW

A spell forces:

DEXTERITY SAVING THROW

The character lacks training with the armor being worn.

Result:

DISADVANTAGE

PART FORTY-THREE — WHAT ABOUT WISDOM OR CHARISMA?

The armor-training penalty specifically refers to D20 Tests involving:

STRENGTH OR DEXTERITY

It doesn't say that untrained armor automatically gives Disadvantage on:

INTELLIGENCE

WISDOM

or:

CHARISMA

D20 Tests.

EXAMPLE

Untrained armor wearer makes:

WISDOM (PERCEPTION)

The untrained-armor rule itself doesn't impose:

DISADVANTAGE

on that roll.

PART FORTY-FOUR — THE SPELLCASTING PENALTY IS ABSOLUTE

If you wear Light, Medium, or Heavy Armor and lack training with it:

YOU CAN'T CAST SPELLS

This isn't limited to spells with:

SOMATIC COMPONENTS

It isn't limited to spells using:

SPELL SLOTS

The armor-training rule simply says:

YOU CAN'T CAST SPELLS

while the rule applies.

EXAMPLE — CANTRIP

Wizard without Heavy Armor training puts on:

PLATE ARMOR

Can the Wizard cast:

FIRE BOLT?

NO

The untrained-armor rule says:

YOU CAN'T CAST SPELLS

RITUAL?

The rule doesn't create a Ritual exception.

CAN'T CAST SPELLS

SPECIES SPELL?

Still:

A SPELL

No exception is written merely because the spell came from:

SPECIES

rather than Class.

PART FORTY-FIVE — ARMOR TRAINING VERSUS SPELLCASTING CLASS

A spellcaster can cast spells in armor:

IF THEY HAVE THE REQUIRED ARMOR TRAINING

The general armor rule doesn't say:

"SPELLCASTERS CAN NEVER WEAR ARMOR"

It says the problem arises when you wear armor:

WITHOUT TRAINING

EXAMPLE

A character has:

SPELLCASTING

and:

MEDIUM ARMOR TRAINING

They wear:

BREASTPLATE

The untrained-armor spellcasting prohibition:

DOES NOT APPLY

because they are trained with that category.

PART FORTY-SIX — SHIELD TRAINING WORKS DIFFERENTLY

If you hold/use a Shield without:

SHIELD TRAINING

you don't receive:

ITS AC BENEFIT

 

The rule for an untrained Shield is therefore different from the rule for wearing untrained:

LIGHT

MEDIUM

or:

HEAVY ARMOR

PART FORTY-SEVEN — SHIELD

The standard Shield gives:

+2 AC

Weight:

6 LB.

Cost:

10 GP

 

EXAMPLE

Chain Mail:

AC 16

Shield:

+2

Total:

AC 18

assuming:

APPROPRIATE TRAINING

PART FORTY-EIGHT — SHIELD + PLATE

Plate:

AC 18

Shield:

+2

Total:

AC 20

before any other applicable bonuses.

PART FORTY-NINE — SHIELD + LIGHT ARMOR

Studded Leather:

12 + DEX

Dexterity:

+4

Base AC:

12 + 4 =

16

Shield:

+2

Total:

AC 18

if the character has the appropriate training and no other rule prevents use of the Shield.

PART FIFTY — SHIELD DOESN'T REPLACE BASE AC

Armor usually establishes:

BASE AC

A Shield gives:

+2

It doesn't say:

"YOUR BASE AC IS 2"

EXAMPLE

Leather:

11 + Dex 3 =

14

Shield:

+2

Total:

16

PART FIFTY-ONE — SHIELD WITHOUT TRAINING

You can physically hold:

A SHIELD

without training.

But:

YOU DON'T GET ITS AC BONUS

EXAMPLE

Base AC:

15

Untrained Shield:

+0

Final AC remains:

15

from the Shield rule.

PART FIFTY-TWO — ONLY ONE SUIT OF ARMOR

The SRD explicitly states:

A CREATURE CAN WEAR ONLY ONE SUIT OF ARMOR AT A TIME

 

WRONG EXAMPLE

Wear:

LEATHER ARMOR

under:

PLATE ARMOR

and add both AC calculations.

NO

You can wear only:

ONE SUIT OF ARMOR AT A TIME

for these rules.

PART FIFTY-THREE — ONLY ONE SHIELD

A creature can wield only:

ONE SHIELD AT A TIME

 

WRONG EXAMPLE

Two Shields:

+2 +2 = +4 AC

NO

The SRD's rule prevents wielding multiple Shields in this way.

PART FIFTY-FOUR — DONNING AND DOFFING

To:

DON

armor means to:

PUT IT ON

To:

DOFF

armor means to:

TAKE IT OFF

The category determines:

HOW LONG THIS TAKES

 

PART FIFTY-FIVE — LIGHT ARMOR TIME

Light Armor:

1 MINUTE TO DON

and:

1 MINUTE TO DOFF

This applies to:

PADDED

LEATHER

and:

STUDDED LEATHER

IMPORTANT

One minute is:

NOT ONE ACTION

A combat round lasts only seconds.

So putting on an entire suit of Light Armor isn't normally something you accomplish with:

ONE COMBAT ACTION

PART FIFTY-SIX — MEDIUM ARMOR TIME

Medium Armor:

5 MINUTES TO DON

1 MINUTE TO DOFF

EXAMPLE

Putting on:

HALF PLATE

takes:

5 MINUTES

Removing it:

1 MINUTE

PART FIFTY-SEVEN — HEAVY ARMOR TIME

Heavy Armor:

10 MINUTES TO DON

5 MINUTES TO DOFF

EXAMPLE

Plate Armor.

Put it on:

10 MINUTES

Take it off:

5 MINUTES

This is dramatically slower than:

LIGHT ARMOR

PART FIFTY-EIGHT — SHIELD TIME

A Shield is different.

The Armor table says:

UTILIZE ACTION TO DON OR DOFF

 

So unlike a suit of armor:

A SHIELD CAN BE DONNED OR DOFFED WITH AN ACTION

specifically:

THE UTILIZE ACTION

EXAMPLE

Your Shield isn't currently donned.

On your turn:

UTILIZE ACTION

Don the Shield.

You can now gain its AC benefit if you have:

SHIELD TRAINING

and all relevant requirements are met.

PART FIFTY-NINE — DONNING TIME MATTERS BEFORE COMBAT

Suppose a party is:

SURPRISED BY AN ATTACK

while its armored warrior doesn't have their armor donned.

The warrior can't simply say:

"I PUT ON PLATE"

as a free action.

Plate requires:

10 MINUTES

to don.

The party may need to fight:

WITHOUT THAT ARMOR

unless circumstances allow enough time.

PART SIXTY — ARMOR AND REST

The main Armor rules on page 92 establish:

DONNING

DOFFING

AC

TRAINING

STRENGTH

and:

STEALTH

They do not, in this section, create a universal rule saying:

YOU MUST REMOVE ARMOR TO REST

Don't invent such a rule here.

If another rule, feature, adventure circumstance, or GM determination becomes relevant:

APPLY THAT RULE SEPARATELY

PART SIXTY-ONE — COMPARING AC FOR DIFFERENT DEXTERITY SCORES

Armor works differently depending on:

YOUR DEXTERITY

Consider three characters.

CHARACTER A — DEX +0

Studded Leather:

12 + 0 =

12

Half Plate:

15 + 0 =

15

Plate:

18

CHARACTER B — DEX +2

Studded Leather:

12 + 2 =

14

Half Plate:

15 + 2 =

17

Plate:

18

CHARACTER C — DEX +5

Studded Leather:

12 + 5 =

17

Half Plate:

15 + maximum 2 =

17

Plate:

18

This shows the mechanical identities of the categories.

LIGHT ARMOR

Rewards:

HIGH DEXTERITY

MEDIUM ARMOR

Uses Dexterity, but normally only up to:

+2

HEAVY ARMOR

Doesn't use Dexterity in its listed AC calculation.

PART SIXTY-TWO — AC IS NOT THE ONLY CONSIDERATION

Compare:

HALF PLATE

and:

BREASTPLATE

With Dex +2:

Half Plate:

AC 17

Breastplate:

AC 16

Half Plate is better by:

1 AC

But Half Plate imposes:

STEALTH DISADVANTAGE

Breastplate doesn't.

Half Plate costs:

750 GP

Breastplate:

400 GP

So the decision involves:

DEFENSE

STEALTH

COST

and:

WEIGHT

PART SIXTY-THREE — HEAVY ARMOR TRADE-OFFS

Plate gives:

AC 18

without needing Dexterity.

But it also has:

STRENGTH 15

STEALTH DISADVANTAGE

65 LB. WEIGHT

and:

1,500 GP COST

So the highest listed base AC comes with significant:

CHARACTER-BUILDING

and:

EQUIPMENT

considerations.

PART SIXTY-FOUR — DEFENSE FIGHTING STYLE

In Lesson 59, we learned the:

DEFENSE

Fighting Style Feat.

While wearing:

LIGHT

MEDIUM

or:

HEAVY ARMOR

you gain:

+1 AC

EXAMPLE

Plate:

18

Defense:

+1

Shield:

+2

Total:

18 + 1 + 2 =

AC 21

assuming all applicable requirements are satisfied.

IMPORTANT

Defense requires:

ACTUAL ARMOR

A Shield alone doesn't satisfy its requirement.

PART SIXTY-FIVE — BASE AC CALCULATIONS DO NOT STACK

Suppose you have a feature providing:

ANOTHER BASE AC CALCULATION

and you also wear armor.

The general AC rule says:

CHOOSE WHICH BASE AC CALCULATION TO USE

You don't combine multiple base formulas.

EXAMPLE

Suppose one rule gives:

BASE AC 10 + DEX + WIS

and armor says:

12 + DEX

You don't calculate:

10 + DEX + WIS + 12 + DEX

Choose the legal:

BASE AC CALCULATION

that applies.

PART SIXTY-SIX — MONK EXAMPLE

The Monk's Unarmored Defense requires the Monk to be:

NOT WEARING ARMOR

and:

NOT WIELDING A SHIELD

So a Monk who wants to use that particular Class feature must satisfy:

ITS OWN SPECIFIC CONDITIONS

This is another example of:

SPECIFIC CLASS RULES

interacting with:

GENERAL ARMOR RULES

PART SIXTY-SEVEN — PALADIN EXAMPLE

A level 1 Paladin's core traits provide training with:

LIGHT ARMOR

MEDIUM ARMOR

HEAVY ARMOR

and:

SHIELDS

 

Suppose:

Strength:

16

Dexterity:

10

Starting equipment includes:

CHAIN MAIL

and:

SHIELD

Chain Mail:

AC 16

Strength requirement:

13

Paladin Strength:

16

No Speed penalty.

Shield:

+2

Final AC:

18

The Paladin has the necessary:

TRAINING

so the untrained-armor penalties don't apply.

PART SIXTY-EIGHT — LOW-STRENGTH PALADIN EXAMPLE

Same trained Paladin.

Strength:

12

Chain Mail:

STR 13

The Paladin still has:

HEAVY ARMOR TRAINING

so there is no untrained-armor penalty.

But Strength is below:

13

Therefore:

SPEED −10 FEET

These are separate rules.

ARMOR TRAINING

Question:

ARE YOU TRAINED?

STRENGTH REQUIREMENT

Different question:

IS YOUR STRENGTH HIGH ENOUGH?

You can pass one and fail:

THE OTHER

PART SIXTY-NINE — TRAINING DOES NOT REMOVE STEALTH DISADVANTAGE

Suppose you are fully trained with:

PLATE ARMOR

Plate still says:

STEALTH — DISADVANTAGE

Armor Training lets you avoid:

THE UNTRAINED-ARMOR PENALTIES

It doesn't erase other properties listed for:

THAT ARMOR

EXAMPLE

Paladin in Plate.

Heavy Armor training:

YES

Dexterity (Stealth):

STILL DISADVANTAGE

because Plate itself says so.

PART SEVENTY — TRAINING DOES NOT REMOVE STRENGTH REQUIREMENTS

Likewise:

Armor Training:

YES

Strength below listed requirement:

SPEED STILL −10 FEET

Training and Strength are:

INDEPENDENT RULES

PART SEVENTY-ONE — SHIELD TRAINING DOES NOT GIVE ARMOR TRAINING

Training with:

SHIELDS

doesn't automatically mean training with:

HEAVY ARMOR

or:

MEDIUM ARMOR

unless a Class or feature specifically grants those categories too.

PART SEVENTY-TWO — ARMOR TRAINING DOES NOT AUTOMATICALLY GIVE SHIELD TRAINING

Likewise, being trained in:

MEDIUM ARMOR

doesn't itself say:

SHIELD TRAINING

Check the actual Class or feature.

PART SEVENTY-THREE — FULL LIGHT ARMOR EXAMPLE

Rogue.

Dexterity:

18

Modifier:

+4

Studded Leather:

12 + DEX

AC:

12 + 4 =

16

No Stealth Disadvantage.

No Strength requirement.

If the Rogue has appropriate Light Armor training:

NO UNTRAINED PENALTIES

This is a strong example of Light Armor rewarding:

HIGH DEXTERITY

PART SEVENTY-FOUR — FULL MEDIUM ARMOR EXAMPLE

Ranger.

Dexterity:

16

Modifier:

+3

Breastplate:

14 + DEX MOD, MAX 2

Although Dex is +3:

ONLY +2 COUNTS

AC:

14 + 2 =

16

No Stealth Disadvantage.

Add trained Shield:

+2

Total:

AC 18

PART SEVENTY-FIVE — FULL HEAVY ARMOR EXAMPLE

Fighter.

Strength:

18

Dexterity:

8

Modifier:

−1

Plate:

AC 18

Dexterity doesn't reduce it.

Strength requirement:

15

Fighter Strength:

18

No Speed reduction.

Shield:

+2

Total:

AC 20

Stealth:

DISADVANTAGE

PART SEVENTY-SIX — UNTRAINED ARMOR EXAMPLE

Wizard has:

Strength:

10

Dexterity:

16

and no Heavy Armor training.

Wizard dons:

PLATE

The armor provides:

AC 18

but the Wizard lacks:

HEAVY ARMOR TRAINING

Therefore:

DISADVANTAGE

on any D20 Test involving:

STRENGTH OR DEXTERITY

and:

CAN'T CAST SPELLS

Additionally, Plate has:

STRENGTH 15

Wizard Strength:

10

So Speed is reduced by:

10 FEET

And Plate imposes:

DISADVANTAGE ON DEXTERITY (STEALTH)

Several independent armor rules are now affecting:

THE SAME CHARACTER

PART SEVENTY-SEVEN — SAME EFFECT FROM DIFFERENT SOURCES

Suppose the Wizard above makes:

DEXTERITY (STEALTH)

There are two reasons for Disadvantage:

UNTRAINED HEAVY ARMOR

and:

PLATE'S STEALTH ENTRY

But multiple sources of Disadvantage don't make you roll:

THREE D20S

The normal Advantage/Disadvantage rules still apply.

This is why identifying the sources matters, even though:

DISADVANTAGE DOESN'T STACK

PART SEVENTY-EIGHT — BUYING ARMOR

Armor costs range enormously.

Padded:

5 GP

Leather:

10 GP

Ring Mail:

30 GP

Studded Leather:

45 GP

Half Plate:

750 GP

Plate:

1,500 GP

So upgrading armor can become a significant use of:

ADVENTURE TREASURE

SELLING REMINDER

Ordinary equipment normally sells for:

HALF ITS COST

from Lesson 60.

So ordinary Plate with cost:

1,500 GP

normally fetches:

1,500 ÷ 2 =

750 GP

when sold under that rule.

PART SEVENTY-NINE — ARMOR WEIGHT

Armor weight also varies greatly.

Padded:

8 LB.

Leather:

10 LB.

Half Plate:

40 LB.

Chain Mail:

55 LB.

Splint:

60 LB.

Plate:

65 LB.

Shield:

6 LB.

These weights count as:

EQUIPMENT WEIGHT

when relevant to carrying rules.

PART EIGHTY — CHOOSING ARMOR STEP BY STEP

When choosing armor, use this sequence.

STEP 1 — CHECK TRAINING

Are you trained in:

LIGHT?

MEDIUM?

HEAVY?

or:

SHIELDS?

STEP 2 — CALCULATE AC

Light:

BASE + FULL DEX

Medium:

BASE + DEX, MAX +2

Heavy:

FIXED AC

STEP 3 — CHECK STRENGTH

If the armor lists:

STR 13

or:

STR 15

do you meet it?

If not:

SPEED −10 FEET

STEP 4 — CHECK STEALTH

Does the table say:

DISADVANTAGE?

If yes:

DEXTERITY (STEALTH) CHECKS HAVE DISADVANTAGE

STEP 5 — CHECK SHIELD

Do you want:

+2 AC?

If so:

DO YOU HAVE SHIELD TRAINING?

And can your equipment setup accommodate the Shield?

STEP 6 — CHECK COST

Can you afford:

THE ARMOR?

STEP 7 — CHECK WEIGHT

How does it affect your:

TOTAL EQUIPMENT LOAD?

STEP 8 — CHECK DONNING TIME

Do you actually have enough time to:

PUT IT ON?

This can matter enormously when danger arrives unexpectedly.

COMMON BEGINNER MISTAKES

MISTAKE 1 — ADDING ARMOR AC TO 10 + DEX

Armor usually supplies:

A BASE AC CALCULATION

It isn't added on top of your normal 10 + Dex.

MISTAKE 2 — COMBINING TWO BASE AC CALCULATIONS

If multiple base AC formulas are available:

CHOOSE ONE

Don't add them together.

MISTAKE 3 — ADDING FULL DEXTERITY TO MEDIUM ARMOR

Medium Armor normally caps the Dexterity contribution at:

+2

MISTAKE 4 — IGNORING A NEGATIVE DEX MODIFIER IN MEDIUM ARMOR

"Max 2" doesn't mean:

MINIMUM 0

MISTAKE 5 — ADDING DEXTERITY TO HEAVY ARMOR

Heavy Armor has:

FIXED AC

as listed.

MISTAKE 6 — SUBTRACTING NEGATIVE DEXTERITY FROM HEAVY ARMOR

You don't.

Plate remains:

AC 18

even with negative Dexterity.

MISTAKE 7 — THINKING ALL HEAVY ARMOR REQUIRES STRENGTH 15

No.

Ring Mail:

NO STRENGTH REQUIREMENT

Chain Mail:

STR 13

Splint:

STR 15

Plate:

STR 15

MISTAKE 8 — THINKING LOW STRENGTH MEANS YOU CAN'T WEAR THE ARMOR

The listed consequence is:

SPEED −10 FEET

MISTAKE 9 — THINKING LOW STRENGTH REDUCES AC

It doesn't.

MISTAKE 10 — THINKING LOW STRENGTH AUTOMATICALLY GIVES ATTACK DISADVANTAGE

The armor Strength rule says:

SPEED REDUCTION

not Attack Disadvantage.

MISTAKE 11 — THINKING ARMOR TRAINING AND STRENGTH REQUIREMENT ARE THE SAME THING

They are:

SEPARATE RULES

MISTAKE 12 — THINKING TRAINING REMOVES STEALTH DISADVANTAGE

It doesn't.

MISTAKE 13 — THINKING TRAINING REMOVES THE STRENGTH REQUIREMENT

It doesn't.

MISTAKE 14 — WEARING UNTRAINED ARMOR WITHOUT ANY CONSEQUENCE

You have Disadvantage on D20 Tests involving:

STRENGTH OR DEXTERITY

and:

CAN'T CAST SPELLS

MISTAKE 15 — THINKING UNTRAINED ARMOR ONLY AFFECTS ATTACK ROLLS

It affects:

ANY D20 TEST

involving Strength or Dexterity.

MISTAKE 16 — THINKING UNTRAINED ARMOR GIVES DISADVANTAGE ON EVERY D20 TEST

The rule names:

STRENGTH OR DEXTERITY

MISTAKE 17 — THINKING A SPELLCASTER CAN NEVER CAST IN ARMOR

The restriction applies when wearing armor:

WITHOUT TRAINING

MISTAKE 18 — THINKING CANTRIPS IGNORE THE UNTRAINED-ARMOR SPELL RESTRICTION

A Cantrip is still:

A SPELL

MISTAKE 19 — THINKING A SHIELD GIVES +2 AC WITHOUT TRAINING

It doesn't.

You need:

SHIELD TRAINING

to gain its AC benefit.

MISTAKE 20 — THINKING SHIELD TRAINING IS AUTOMATIC WITH ARMOR TRAINING

Check:

THE ACTUAL FEATURE

MISTAKE 21 — THINKING TWO SHIELDS GIVE +4 AC

A creature can wield only:

ONE SHIELD AT A TIME

MISTAKE 22 — WEARING MULTIPLE SUITS OF ARMOR AND ADDING THEIR AC

A creature can wear only:

ONE SUIT OF ARMOR AT A TIME

MISTAKE 23 — THINKING PADDED ARMOR HAS NORMAL STEALTH

Padded imposes:

DISADVANTAGE

MISTAKE 24 — THINKING EVERY MEDIUM ARMOR IMPOSES STEALTH DISADVANTAGE

Only:

SCALE MAIL

and:

HALF PLATE

do so in the main table.

MISTAKE 25 — THINKING BREASTPLATE HAS STEALTH DISADVANTAGE

It doesn't have it listed.

MISTAKE 26 — THINKING HEAVY ARMOR DOESN'T AFFECT STEALTH

Every Heavy Armor in the table imposes:

DISADVANTAGE ON DEXTERITY (STEALTH)

MISTAKE 27 — THINKING A SHIELD SETS YOUR AC TO +2

It gives:

+2 AC

It isn't a base AC calculation of 2.

MISTAKE 28 — THINKING LIGHT ARMOR TAKES ONE ACTION TO PUT ON

Light Armor takes:

1 MINUTE

to don.

MISTAKE 29 — THINKING MEDIUM ARMOR TAKES ONE MINUTE TO PUT ON

Medium Armor takes:

5 MINUTES TO DON

MISTAKE 30 — THINKING HEAVY ARMOR CAN BE DONNED DURING ONE NORMAL TURN

Heavy Armor takes:

10 MINUTES TO DON

MISTAKE 31 — THINKING HEAVY ARMOR TAKES TEN MINUTES TO REMOVE

It takes:

5 MINUTES TO DOFF

MISTAKE 32 — THINKING SHIELDS TAKE A MINUTE TO DON

A Shield uses:

UTILIZE ACTION

to don or doff.

MISTAKE 33 — CHOOSING ARMOR ONLY BY AC

Also consider:

TRAINING

DEXTERITY

STRENGTH

STEALTH

WEIGHT

COST

and:

DONNING TIME

QUICK RECAP

There are three armor categories:

LIGHT

MEDIUM

HEAVY

plus:

SHIELDS

LIGHT ARMOR

Padded:

11 + DEX

Leather:

11 + DEX

Studded Leather:

12 + DEX

Full Dexterity modifier applies.

Padded imposes:

STEALTH DISADVANTAGE

MEDIUM ARMOR

Hide:

12 + DEX, MAX +2

Chain Shirt:

13 + DEX, MAX +2

Scale Mail:

14 + DEX, MAX +2

Breastplate:

14 + DEX, MAX +2

Half Plate:

15 + DEX, MAX +2

Stealth Disadvantage:

SCALE MAIL

and:

HALF PLATE

HEAVY ARMOR

Ring Mail:

AC 14

Chain Mail:

AC 16

Splint:

AC 17

Plate:

AC 18

Heavy Armor does not add:

DEXTERITY MODIFIER

Every Heavy Armor in the table imposes:

STEALTH DISADVANTAGE

STRENGTH REQUIREMENTS

Chain Mail:

STR 13

Splint:

STR 15

Plate:

STR 15

Below requirement:

SPEED −10 FEET

ARMOR TRAINING

Wear Light, Medium, or Heavy Armor without training:

DISADVANTAGE

on D20 Tests involving:

STRENGTH OR DEXTERITY

and:

YOU CAN'T CAST SPELLS

SHIELD

Bonus:

+2 AC

but only if you have:

SHIELD TRAINING

Only:

ONE SHIELD AT A TIME

ARMOR LIMIT

Only:

ONE SUIT OF ARMOR AT A TIME

DON / DOFF

Light:

1 MINUTE / 1 MINUTE

Medium:

5 MINUTES / 1 MINUTE

Heavy:

10 MINUTES / 5 MINUTES

Shield:

UTILIZE ACTION / UTILIZE ACTION

 

PRIME HERO CHALLENGE

Four adventurers are preparing to enter a ruined fortress.

HERO A

Dexterity:

18

Light Armor training.

Wears:

STUDDED LEATHER

Dex modifier:

+4

AC:

12 + 4 =

AC 16

HERO B

Dexterity:

18

Medium Armor training.

Wears:

HALF PLATE

Dex modifier:

+4

But Medium Armor maximum:

+2

AC:

15 + 2 =

AC 17

Stealth:

DISADVANTAGE

HERO C

Strength:

14

Heavy Armor training.

Speed:

30 FEET

Wears:

PLATE

Plate:

AC 18

Strength requirement:

15

Hero Strength:

14

Therefore Speed:

30 − 10 =

20 FEET

Stealth:

DISADVANTAGE

HERO D

Wizard without Heavy Armor training.

Dexterity:

16

Puts on:

CHAIN MAIL

What happens?

Chain Mail provides:

AC 16

But the Wizard lacks:

HEAVY ARMOR TRAINING

Therefore:

DISADVANTAGE

on D20 Tests involving Strength or Dexterity,

and:

CAN'T CAST SPELLS

If the Wizard's Strength is also below:

13

Speed is additionally reduced by:

10 FEET

BONUS QUESTION

Hero B also has:

SHIELD TRAINING

and dons a Shield.

Half Plate AC:

17

Shield:

+2

Total:

AC 19

LESSON 64 — KEY TAKEAWAYS

Armor creates:

DIFFERENT DEFENSIVE STRATEGIES

Light Armor says:

RELY ON DEXTERITY

Medium Armor says:

COMBINE ARMOR WITH SOME DEXTERITY

Heavy Armor says:

RELY ON THE ARMOR'S FIXED AC

And a Shield says:

ADD +2 AC

if you have the required training.

BUT AC IS ONLY THE BEGINNING

Armor can affect:

SPEED

STEALTH

SPELLCASTING

STRENGTH AND DEXTERITY D20 TESTS

EQUIPMENT WEIGHT

and:

PREPARATION TIME

So whenever you choose armor, ask:

WHAT IS MY AC?

HOW DOES DEXTERITY AFFECT IT?

DO I HAVE THE REQUIRED TRAINING?

DO I MEET THE STRENGTH REQUIREMENT?

DOES IT HURT MY STEALTH?

CAN I USE A SHIELD?

HOW LONG DOES IT TAKE TO PUT ON?

HOW MUCH DOES IT COST?

and:

HOW MUCH DOES IT WEIGH?

Once you answer those questions:

YOU UNDERSTAND YOUR DEFENSE

NEXT LESSON

LESSON 65 — TOOLS

Armor protects the adventurer.

Weapons defeat enemies.

But adventurers also need to:

BUILD

REPAIR

PICK LOCKS

CREATE

PLAY MUSIC

DISGUISE THEMSELVES

NAVIGATE

and perform many other practical tasks.

Lesson 65 will cover the complete SRD:

TOOL SYSTEM

including:

ARTISAN'S TOOLS

OTHER TOOLS

GAMING SETS

MUSICAL INSTRUMENTS

and:

TOOL PROFICIENCY

We will learn how Tool Proficiency interacts with:

ABILITY CHECKS

what happens when both:

A SKILL

and:

A TOOL

apply to the same check,

and how the SRD's individual tools specify:

ABILITY

UTILIZE ACTIONS

CRAFTING

COST

and:

WEIGHT

before Lesson 66 moves into:

ADVENTURING GEAR

SRD 5.2.1 ATTRIBUTION

This work includes material from the System Reference Document 5.2.1 (“SRD 5.2.1”) by Wizards of the Coast LLC, available at https://www.dndbeyond.com/srd. The SRD 5.2.1 is licensed under the Creative Commons Attribution 4.0 International License, available at https://creativecommons.org/licenses/by/4.0/legalcode.