D&D 5E Determining CR / XP for NPC

[MNblockhead]

I'm new to 5th edition and have not role-played for a long time until I bought 5e and started a campaign. So, I'm rusty as a DM.

My players characters are now into the 2nd tier of play (most around 6th level) and I create my own adventures in my own world. I'm getting to the point where they are facing more more complex antagonists, where I can't easily look at the Monster Manual and the DMG tables and come up with the appropriate CR and XP. Also, I want to make for some very challenging, climatic battles without making it almost impossible for the party to beat.

The DMG's Creating a Monster section (DMG 273) is not so helpful to me when, say, I create a an evil cleric basically using the PHB class-creation rule to build.

I would appreciate anything you can share about both your read of the DMG on the and *your* personal approach.

What would, for example, a 9th level fighter's CR and XP be? In terms of balance and challenges, if you have 4 6th-level party members, would 4 6th-level NPCs be a considered a hard challenge?

Thanks for any tips and experience you can share here.

 

[Quickleaf]

[MENTION=6796661]MNblockhead[/MENTION] My quick and dirty guideline is warrior type NPCs have a CR very roughly equal to 1/3 their level, whereas casters with serious firepower have a CR very generally equal to 1/2 their level. However, there's tons of variables that can throw this off (particularly AC and attack bonus), so I only would suggest using it if you absolutely don't have time to run the numbers yourself.

By "running the numbers", here's what I mean... See page 274 of the DMG to follow along...

9th level fighter (champion)
I'm assuming a very robust warrior with 20 strength, 18 constitution, 14 dexterity, dueling fighting style, no magic items or feats, wearing half-plate, wielding a long sword and shield in a scenario where he can engage in meaningful melee combat each round

HP = 100 (9d10+36 con+14.5 second wind)
AC = 19 (15+2 dex+2 shield)
Longsword +9 to hit; two attacks at 11.5 (1d8+7) damage each
DPR = 31
Saving throws = treat him as having 3 saving throws, thanks to Indomitable

[SBLOCK=DPR calculation]Damage per round (DPR), calculated over 3 rounds
I'm not factoring to hit values or average AC of "appropriate CR" opponents, since that's built into the DMG calculations.

1st round (action surge): four longsword attacks = 4(11.5) = 46
2nd round: two longsword attacks = 2(11.5) = 23
3rd round: two longsword attacks = 2(11.5) = 23

Average DPR = (46 + 23 +23) / 3 = 30.6 ≈ 31[/SBLOCK]

Defense CR = 6: 2 (for hp 100), with 4 bumps up (for effective AC 21 thanks to three saves I estimated from Indomitable)
Offense CR = 6: 4 (for damage 31), with 2 bumps up (for attack +9)

Total CR = 6: (6 + 6) / 2 = 6

Against your four-man party of 6th-level PCs, this 9th-level fighter NPC would be a pushover unless encountered with some friends of his own.

EDIT: Revised thanks to ExploderWizard catching my error.

 

[ExploderWizard]

[MENTION=6796661]MNblockhead[/MENTION] My quick and dirty guideline is warrior type NPCs have a CR very roughly equal to 1/3 their level, whereas casters with serious firepower have a CR very generally equal to 1/2 their level. However, there's tons of variables that can throw this off (particularly AC and attack bonus), so I only would suggest using it if you absolutely don't have time to run the numbers yourself.

By "running the numbers", here's what I mean... See page 274 of the DMG to follow along...

9th level fighter (champion)
I'm assuming a very robust warrior with 20 strength, 18 constitution, 14 dexterity, dueling fighting style, no magic items or feats, wearing half-plate, wielding a long sword and shield in a scenario where he can engage in meaningful melee combat each round

HP = 100 (9d10+36 con+14.5 second wind)
AC = 19 (15+2 dex+2 shield)
Longsword +9 to hit; two attacks at 11.5 (1d8+7) damage each
DPR = 27
Saving throws = treat him as having 3 saving throws, thanks to Indomitable

[SBLOCK=DPR calculation]Damage per round (DPR), calculated over 3 rounds
I'm not factoring to hit values or average AC of "appropriate CR" opponents, since that's built into the DMG calculations.

1st round (action surge): three longsword attacks = 3(11.5) = 34.5
2nd round: two longsword attacks = 2(11.5) = 23
3rd round: two longsword attacks = 2(11.5) = 23

Average DPR = (34.5 + 23 +23) / 3 = 26.8 ≈ 27[/SBLOCK]

Defense CR = 6: 2 (for hp 100), with 4 bumps up (for effective AC 21 thanks to three saves I estimated from Indomitable)
Offense CR = 6: 4 (for damage 27), with 2 bumps up (for attack +9)

Total CR = 6 (6 + 6) / 2 = 6

Against your four-man party of 6th-level PCs, this 9th-level fighter NPC would be a pushover unless encountered with some friends of his own.

I think your DPR calculation is a tad off but not by much. Action surge grants another attack action, not just a single attack. So this sample fighter would get 4 attacks in round 1 for an average damage of 46. This translates to an average DPR of 30 instead of 27, so it won't really alter the CR.

My approach to NPCs is to start with base stats based on how tough it is as a monster then add in class abilities before calculating final CR. I have found that most NPCs built more or less as a PC don't have the hit points to be durable enough for a challenge, particularly casters & rogues.

 

[Oofta]

I've been struggling with this myself, and have two basic approaches based on what I want to accomplish with my NPC.

One option is to simply reflavor an existing monster. Usually I do this because I'm in a hurry, but I just simply take the stats and abilities of a monster and give them to an NPC. The NPC may be infused with magical power, or perhaps just using one-off consumable items (if for example the base monster has a breath weapon).

The other way I do it is to follow the same rules that you use for upgrading monsters. So in the case of creating a 9th level fighter, I start with a gladiator. If I check the DMG page 274, I just go by the chart and determine differences between level 5 and 9. So I add +1 prof bonus, +1 AC, 60 HP, +1 attack, around 24 points of damage per round and +1 save DC (for knocked prone).

The most difficult part is figuring out damage. I up the base dice, increase ability damage, add extra attacks as necessary.

This seems to work reasonably well for me, although I tend to crank of the challenge level with NPCs built this way.

Spellcasters are more difficult to level up this way and I look at spells and spell-like abilities of monsters close to the target CR. Or I just kind of guess (which I know is not particularly helpful). As a general rule of thumb I just make spellcasters several levels higher than the PCs for purposes of what spells they use and use the same rules for upgrading other NPCs.

 

[BoldItalic]

...
In terms of balance and challenges, if you have 4 6th-level party members, would 4 6th-level NPCs be a considered a hard challenge?

If you were to pitch the party against an identical party of clones, assuming equally good play, and if both sides were determined to fight to the death, there's a 50% chance of TPK. That would be a deadly encounter. If the goals of the NPCs are not to fight to the death, but merely to delay the party or cause the party to waste a certain amount of resources, then the encounter is easier than that. A lot depends on how you decide when the encounter ends.

One difference to previous editions is that mechanical morale checks to determine when an encounter ends are less of a feature of 5e, although there are optional morale rules in the DMG on p.273. The encounter difficulty guidelines don't assume that morale checks are used, but they don't assume any particular NPC goals either.

If you think of it in those terms, you only have to ask: is this set of monsters going to survive long enough to achieve the goals I want them to achieve? And that means deciding what the encounter is for in the context of the adventure as a whole.

 

[MNblockhead]

Thanks everyone. These are very helpful. Quickleaf, thanks for helping step the example fighter through the DMG Creating a Monster process. Very helpful. I find it much more difficult, however, to run the numbers in this way with spell casters, as Oofta also points out. So much of the challenge of fighting a higher-level spell caster is all of the things they can do to hold you, slow you, buff themselves, etc. I would almost need to war-game a whole battle and then average things up. Even then, just looking at average DPR per round seems very misleading.

What I'm leaning toward is more of quickleaf's quick rules of thumb (warriors CR = 1/3 of their level, etc.).

BoldItalics approach is how I try to approach it, but I'm in a situation where I'm DMing a group of players that are much more hardcore gamers than I. While they are not hard-core min/maxers, they certainly are better at getting the most of their characters' powers. That's why I do try to go through the DMG encounter and monster-building rules as much as possible as WoTC has seem to have done a good job with game balance.

For encounters that are more important to the story, I'm thinking of just putting everything to Herolabs and war-gaming a couple battles in its tactical console to get an idea of how difficult and drawn out the battles will be.

 

[Quickleaf]

Thanks everyone. These are very helpful. Quickleaf, thanks for helping step the example fighter through the DMG Creating a Monster process. Very helpful. I find it much more difficult, however, to run the numbers in this way with spell casters, as Oofta also points out. So much of the challenge of fighting a higher-level spell caster is all of the things they can do to hold you, slow you, buff themselves, etc. I would almost need to war-game a whole battle and then average things up. Even then, just looking at average DPR per round seems very misleading.

Well, for determining the CR of spellcasters, mostly you're looking at raw damage output and guesstimating how many creatures are trapped in area of effect spells. You can also find approximations for some spells on the DMG monster features table p.280-281. For spellcasters who exert a lot of control effects, it's sometimes more helpful to think of those globally in the same terms you'd think of setting an entire encounter in knee-deep water that acts as difficult terrain; in other words, shift the entire difficulty of the encounter up a step if their control is really good. Anything beyond that and you're firmly in the realm of DMing art, not mathematics.

What I'm leaning toward is more of quickleaf's quick rules of thumb (warriors CR = 1/3 of their level, etc.).

Yep, sounds like you've got a good approach. I ran the numbers on your NPC Fighter, because I wanted to illustrate the "margin of error" on my rule of thumb. Simply by giving a 9th level warrior-type NPC higher ability scores, good equipment, and Action Surge, I ended up with CR 6 (which is 2/3rds levels, rather than 1/3rd which would be CR 3). That's a pretty big variation, isn't it?

To be fair, there's tons of variation (surprise, terrain, magic items, play style, house rules, etc) built into 5th edition's challenge system, and lots of people report experienced tactical-minded players who work well together taking on opposition way beyond what the rules would suggest.

Besides keeping in mind your group's skill as players, I would also advise paying attention to how fresh their PCs are. The encounters they can handle when they're fresh can be a lot more difficult than the ones they can handle when they've already been taxed by a few encounters.

 

[GX.Sigma]

9th level fighter (champion)
I'm assuming a very robust warrior with 20 strength, 18 constitution, 14 dexterity, dueling fighting style, no magic items or feats, wearing half-plate, wielding a long sword and shield in a scenario where he can engage in meaningful melee combat each round

HP = 100 (9d10+36 con+14.5 second wind)
AC = 19 (15+2 dex+2 shield)
Longsword +9 to hit; two attacks at 11.5 (1d8+7) damage each
DPR = 31
Saving throws = treat him as having 3 saving throws, thanks to Indomitable

[SBLOCK=DPR calculation]Damage per round (DPR), calculated over 3 rounds
I'm not factoring to hit values or average AC of "appropriate CR" opponents, since that's built into the DMG calculations.

1st round (action surge): four longsword attacks = 4(11.5) = 46
2nd round: two longsword attacks = 2(11.5) = 23
3rd round: two longsword attacks = 2(11.5) = 23

Average DPR = (46 + 23 +23) / 3 = 30.6 ≈ 31[/SBLOCK]

Defense CR = 6: 2 (for hp 100), with 4 bumps up (for effective AC 21 thanks to three saves I estimated from Indomitable)
Offense CR = 6: 4 (for damage 31), with 2 bumps up (for attack +9)

Total CR = 6: (6 + 6) / 2 = 6

FWIW, I made a slightly different build, and also got CR 6 for a 9th-level fighter.

[sblock="Ftr 1-9 Stat Blocks"]Veteran (Fighter 1)
XP 100 (CR 1/2: DCR 1, OCR 1/2)
Medium humanoid
Initiative +1

DEFENSE
AC: 19 (chainmail and shield; defensive fighting style)
hp: 12 (1d10 + 2)

OFFENSE
Speed: 30 ft.
Melee Attack – Longsword: +4 to hit; 6 (1d8 + 2) slashing damage.
Second Wind (1/rest): The fighter can regain 6 (1d10 + 1) hp as a bonus action.

STATISTICS
Str 15 (+2), Dex 13 (+1), Con 14 (+2), Int 8 (-2), Wis 10 (+0), Cha 12 (+1)
Saves: Strength +4, Constitution +4
Skills: Athletics +4, Intimidation +3, Perception +2, Survival +2
Senses: passive perception 12

Warrior (Fighter 2)
XP 200 (CR 1: DCR 1, OCR 1/2)
Medium humanoid
Initiative +1

DEFENSE
AC: 19 (chainmail and shield; defensive fighting style)
hp: 19 (2d10 + 4)

OFFENSE
Speed: 30 ft.
Melee Attack – Longsword: +4 to hit; 6 (1d8 + 2) slashing damage.
Second Wind (1/rest): The fighter can regain 7 (1d10 + 2) hp as a bonus action.
Action Surge (1/rest): The fighter can take an additional action.

STATISTICS
Str 15 (+2), Dex 13 (+1), Con 14 (+2), Int 8 (-2), Wis 10 (+0), Cha 12 (+1)
Saves: Strength +4, Constitution +4
Skills: Athletics +4, Intimidation +3, Perception +2, Survival +2
Senses: passive perception 12

Swordsman (Fighter 3)
XP 200 (CR 1: DCR 1; OCR 1)
Medium humanoid
Initiative +1

DEFENSE
AC: 20 (banded and shield; defensive fighting style)
hp: 27 (3d10 + 6)

OFFENSE
Speed: 30 ft.
Melee Attack – Longsword: +4 to hit; 6 (1d8 + 2) slashing damage.
Second Wind (1/rest): The fighter can regain 8 (1d10 + 3) hp as a bonus action.
Action Surge (1/rest): The fighter can take an additional action.

STATISTICS
Str 15 (+2), Dex 13 (+1), Con 14 (+2), Int 8 (-2), Wis 10 (+0), Cha 12 (+1)
Saves: Strength +4, Constitution +4
Skills: Athletics +4, Intimidation +3, Perception +2, Survival +2
Senses: passive perception 12

TRAITS
Improved Critical: 19-20

Hero (Fighter 4)
XP 450 (CR 2; DCR 2, OCR 2)
Medium humanoid
Initiative +1

DEFENSE
AC: 20 (banded and shield; defensive fighting style)
hp: 34 (4d10 + 8)

OFFENSE
Speed: 30 ft.
Melee Attack – Longsword: +5 to hit; 7 (1d8 + 3) slashing damage.
Second Wind (1/rest): The fighter can regain 9 (1d10 + 4) hp as a bonus action.
Action Surge (1/rest): The fighter can take an additional action.

STATISTICS
Str 17 (+3), Dex 13 (+1), Con 14 (+2), Int 8 (-2), Wis 10 (+0), Cha 12 (+1)
Saves: Strength +5, Constitution +4
Skills: Athletics +5, Intimidation +3, Perception +2, Survival +2
Senses: passive perception 12

TRAITS
Improved Critical: 19-20

Swashbuckler (Fighter 5)
XP 700 (CR 3; DCR 4, OCR 3)
Medium humanoid
Initiative +1

DEFENSE
AC: 21 (plate and shield; defensive fighting style)
hp: 42 (5d10 + 10)

OFFENSE
Speed: 30 ft.
Multiattack: The fighter makes two longsword attacks.
Melee Attack – Longsword: +6 to hit; 7 (1d8 + 3) slashing damage.
Second Wind (1/rest): The fighter can regain 10 (1d10 + 5) hp as a bonus action.
Action Surge (1/rest): The fighter can take an additional action.

STATISTICS
Str 17 (+3), Dex 13 (+1), Con 14 (+2), Int 8 (-2), Wis 10 (+0), Cha 12 (+1)
Saves: Strength +6, Constitution +5
Skills: Athletics +6, Intimidation +4, Perception +3, Survival +3
Senses: passive perception 13

TRAITS
Improved Critical: 19-20

Myrmidon (Fighter 6)
XP 1,100 (CR 4: DCR 4, OCR 4)
Medium humanoid
Initiative +1

DEFENSE
AC: 21 (plate and shield; defensive fighting style)
hp: 49 (6d10 + 12)

OFFENSE
Speed: 30 ft.
Multiattack: The fighter makes two longsword attacks.
Melee Attack – Longsword: +7 to hit; 8 (1d8 + 4) slashing damage.
Second Wind (1/rest): The fighter can regain 11 (1d10 + 6) hp as a bonus action.
Action Surge (1/rest): The fighter can take an additional action.

STATISTICS
Str 19 (+4), Dex 13 (+1), Con 14 (+2), Int 8 (-2), Wis 10 (+0), Cha 12 (+1)
Saves: Strength +7, Constitution +5
Skills: Athletics +7, Intimidation +4, Perception +3, Survival +3
Senses: passive perception 13

TRAITS
Improved Critical: 19-20

Champion (Fighter 7)
XP 1,100 (CR 4: DCR 4, OCR 4)
Medium humanoid
Initiative +2

DEFENSE
AC: 21 (plate and shield; defensive fighting style)
hp: 57 (7d10 + 14)

OFFENSE
Speed: 30 ft.
Multiattack: The fighter makes two longsword attacks.
Melee Attack – Longsword: +7 to hit; 8 (1d8 + 4) slashing damage.
Second Wind (1/rest): The fighter can regain 12 (1d10 + 7) hp as a bonus action.
Action Surge (1/rest): The fighter can take an additional action.

STATISTICS
Str 19 (+4), Dex 13 (+1), Con 14 (+2), Int 8 (-2), Wis 10 (+0), Cha 12 (+1)
Saves: Strength +7, Constitution +5
Skills: Athletics +7, Intimidation +4, Perception +3, Survival +3
Senses: passive perception 13

TRAITS
Improved Critical: 19-20
Remarkable Athlete: The fighter adds +1 to Strength, Dexterity, and Wisdom checks it’s not proficient with.

Superhero (Fighter 8)
XP 1,800 (CR 5: DCR 5, OCR 5)
Medium humanoid
Initiative +2

DEFENSE
AC: 21 (plate and shield; defensive fighting style)
hp: 64 (8d10 + 16)

OFFENSE
Speed: 30 ft.
Multiattack: The fighter makes two longsword attacks.
Melee Attack – Longsword: +8 to hit; 9 (1d8 + 5) slashing damage.
Second Wind (1/rest): The fighter can regain 13 (1d10 + 8) hp as a bonus action.
Action Surge (1/rest): The fighter can take an additional action.

STATISTICS
Str 20 (+5), Dex 13 (+1), Con 15 (+2), Int 8 (-2), Wis 10 (+0), Cha 12 (+1)
Saves: Strength +8, Constitution +5
Skills: Athletics +8, Intimidation +4, Perception +3, Survival +3
Senses: passive perception 13

TRAITS
Improved Critical: 19-20
Remarkable Athlete: The fighter adds +1 to Strength, Dexterity, and Wisdom checks it’s not proficient with.

Lord (Fighter 9)
XP 2,300 (CR 6: DCR 6, OCR 5)
Medium humanoid
Initiative +3

DEFENSE
AC: 21 (plate and shield; defensive fighting style)
hp: 72 (9d10 + 18)

OFFENSE
Speed: 30 ft.
Multiattack: The fighter makes two longsword attacks.
Melee Attack – Longsword: +9 to hit; 9 (1d8 + 5) slashing damage.
Second Wind (1/rest): The fighter can regain 14 (1d10 + 9) hp as a bonus action.
Action Surge (1/rest): The fighter can take an additional action.

STATISTICS
Str 20 (+5), Dex 13 (+1), Con 15 (+2), Int 8 (-2), Wis 10 (+0), Cha 12 (+1)
Saves: Strength +9, Constitution +6
Skills: Athletics +9, Intimidation +5, Perception +4, Survival +4
Senses: passive perception 14

TRAITS
Improved Critical: 19-20
Remarkable Athlete: The fighter adds +2 to Strength, Dexterity, and Wisdom checks it’s not proficient with.[/sblock]

 

[S'mon]

The back of MM NPCs typically have Wizard CR = 2/3 casting level, warrior CR = 1/3 hit dice (d8 dice). A Fighter is going to be in between those two, probably around CR = 1/2 hit dice if not much optimised. A solo Cleric* would likely be similar, while a Barbarian might be closer to CR = 2/3 level.

*Had a Cleric BBEG IMC... he died in round 1 before he could do anything.

 

[MNblockhead]

Do any of you use HeroLab. I was putting some of these into HL as NPCs and the CR ratings are similar to what you guys are coming up with. I've asked on the HL board how this is calculated. I've just started using HeroLabs and am getting comfortable with just accepting the CR value it calculates. One glaring error is that HL doesn't apply multipliers based on the number of enemies. But when looking at an individual NPCs CR, it seems useful...I can apply the multiplier myself easy enough.