D&D 5E Questions about the 'new' Monster Math as compared to 3.x

[Herobizkit]

In an effort to show my players that combat isn't the be and end-all of D&D, I volunteered to DM a 5e starter campaign abd opted to use 3.0's premier module, The Sunless Citadel, as a primer.

At the time, only the Basic PDF was available and so I had no 5e monsters to use. Struggling to figure out what to do, I turned to EnWorld and found this thread about how to convert 3.x monsters on the fly to 5e.

Then the Hoard of the Dragon Queen PDF came out. And what a difference.

As an example, take a gander at the Hobgoblin, a critter that came up enough to matter in my run. I'm going to post the comparisons directly beside one another like so [3e | 5e].

AC 15 (+1 Dex, +3 studded leather, +1 light shield) | AC 18 (chain mail [16], shield [+2])

HP 1d8+2 (6 average) | HP 2d8+2 (11 average)

Attack: Longsword +2 melee (1d8+1) or javelin +2 (1d6+1) | longsword +3 (1d8+1 or 1d10+1 if 2-handed) or longbow +3 (1d8+1) PLUS 2d6 for 'sneak attack' if target is engaged with an ally

CR: 1/2 | 1/2

I find it difficult to believe that two hobgoblins would be a fair challenge to a party of five (♪ Closer to freeeee...) and even less fair to a party of four. Speaking of, anyone know if the baseline assumption is 4 or 5 party members?

And don't get me started on comparing a 3.x Wyrmling White Dragon to a 5e Wyrmling Red Dragon.

Question is, why do 5e monsters seem to hit harder but less often, while players hit more often but not necessarily as hard? Is this how it's "supposed" to be?

I'm no number-cruncher, but I assume there are many who can help me make sense of 5e's design philosophy...

Anyone? Anyone? Bueller?

 

[77IM]

Search for "bounded accuracy." The TL;DR is that attack and AC numbers, for both players and monsters, is in a much narrower range, so the primary means of representing level are damage and hit points. This allows monsters to stay relevant across a larger range of levels.

That said, the hobgoblin's +2d6 damage thing struck me as a really powerful ability for such a low-level monster. It puuhes their average damage up to around 12.5 points, which is enough to one-shot most 1st-level PCs. If you do the monster XP math, a pair of them is exactly a "hard" encounter for 4 1st-level characters. So I guess that makes sense but it leaves me wondering wtf the CR 1/2 number is for.

 

[jadrax]

That said, the hobgoblin's +2d6 damage thing struck me as a really powerful ability for such a low-level monster. It puuhes their average damage up to around 12.5 points, which is enough to one-shot most 1st-level PCs. If you do the monster XP math, a pair of them is exactly a "hard" encounter for 4 1st-level characters. So I guess that makes sense but it leaves me wondering wtf the CR 1/2 number is for.

The Challenge 1/2 means that two of them should be a hard encounter for a level 1 party of 4 PCs...

 

[Trickster Spirit]

Yes, 5E's CR is not 3E's CR.

In 3E, a monster's CR was roughly calculated to consume roughly 1/4 of a party's resources (3E CR was admittedly borked, so sometimes it worked out that way, but a lot of time not). This assumption meant players were expected to steamroll level-appropriate encounters as long as they had the aforementioned resources to spend on it. Using that as a baseline, you could throw an over-CR encounter at characters to make for a boss fight in which they'd need to expend all of their resources at once, or an under-CR encounter to provide some fun dice-rolling with minimal impact on the rest of the evening's combats.

Whereas in 5E, a monster's CR is it's "must be this tall to ride" sign - a party could face an ogre at level 2 and come out of the encounter alive, but it wouldn't be easy. If they don't play it smart and the dice are cruel they could be looking at casualties. You don't throw over-CR monsters at characters in 5E, or if you do, you do it knowing it could lead to a TPK.

I get the feeling a lot of the discussion about 5E, especially about character balance, is still rooted in 3E assumptions - taking it for granted that spells work the same way, for example. Treating CR as it was in 3E is another one of those mistaken assumptions - they share the same name across editions, but they indicate very different things.

 

[ExploderWizard]

Monster math.......Heh.

Halloween is just around the corner. Lets do a little monster math!


I was working on my game, late one night
When my eyes beheld,a nagging sight

For my monster from the page began to rise
And suddenly to my surprise

He did the math, he did the monster math
The monster math, it was a campaign smash
He did the math, it caught on in a flash
He did the math, he did the monster math

From my module pages and the encounter keys
To my wandering charts,which are the bees' knees
The monsters all came bringing Orcus with'em
To get a fix from my algorithim

They did the math, they did the monster math
The monster math, it was a campaign smash
They did the math, it caught on in a flash
They did the math, They did the monster math

The monsters were having fun
Calculations had just begun
The formulas were working
The testing had been done

The game was rockin all were diggin the fights
The orcs and goblins caused a dreadful fright
Bounded accuracy was about to arrive
With their special guest, the flat math jive.

They worked the math, they worked the monster math
The monster math, it was a campaign smash
They worked the math, it caught on in a flash
They worked the math, they worked the monster math

Out from its coffin 4th's voice did ring
Seems it was troubled by just one thing
Opened the lid and shook its fist and said
" Whatever happened to my inflated bonus twist?"

It's now the math, it's now the monster math
The monster math, it was a campaign smash
It's now the math, it caught on in a flash
It's now the math, it's now the monster math

Now everything's cool 4th is part of the band
And my monster math is the hit of the land
For you the player this math was meant too
When you open the door, tell them Gary sent you.

Then you can math, then you can monster math
The monster math, and do my campain smash
Then you can math, you'll catch on in a flash
Then you can math, then you can monster math

 

[DEFCON 1]

That said, the hobgoblin's +2d6 damage thing struck me as a really powerful ability for such a low-level monster. It puuhes their average damage up to around 12.5 points, which is enough to one-shot most 1st-level PCs. If you do the monster XP math, a pair of them is exactly a "hard" encounter for 4 1st-level characters. So I guess that makes sense but it leaves me wondering wtf the CR 1/2 number is for.

The thing we also need to remember, especially when it comes to low-level encounters... is that the definition of "Hard" can and will be interpreted several different ways.

An encounter might be considered "Hard" because they are going to pump out a lot of damage that will apply to everyone in a party, knocking out a lot of their resources over time because it takes so long for the fight to end. High AC but low multi-target damage would accomplish this. Everyone gets pounded over time, but the risk of insta-kill is low.

An encounter might also be considered "Hard" because while the enemies seem like paper and could conceivably get eliminated in a short period of time (due to Surprise, high initiative rolls, lucky attack rolls etc.)... they also have massive damage attacks that could insta-kill someone if the circumstances are right and everything falls into place.

For the 5E hobgoblin... the CR is 1/2... meaning that 2 hobgoblins would be a hard encounter for a 1st level party. Now more often than not... a party will roll such that they might steamroll right over these two hobgoblins so fast the hobs might never even get an attack off. So folks might question the definition of it being "Hard". But looks can be deceiving, because with their special ability of Martial Advantage-- your basic sneak attack 2d6 bonus damage if an ally is within 5' of the enemy-- an attack that includes that ability could easily drop a character straight away. Now the odds of that happening are kind of long if we use the baseline of 2 hobs for 1 party, because both hobs would have to go after one target out of the four or five available. So that extra 2d6 might only rarely occur in a '2 hobs vs a party of four' scenario. But when it did... it could be deadly.

But then once you begin adding MORE hobgobs into the fight... the fight gets exponentially more deadly because the odds of any one hob using Martial Advantage grows and grows. So these additional 2d6s start showing up more and more often, potentially one-shotting characters more and more often.

What DMs are going to have to figure out is that just because a party bumrushes a pair of hobgobs and they die in a single round, doesn't mean that he can start throwing more and more hobs at them and expect the same mopping up result, or just 'some damage spread to everyone'. Because while the odds of an insta-kill are longer with only two... they grow more and more for each additional hob you throw into the mix. And that "Hard" encounter designation is there to tell us that. The entire party might not take a pounding, but a single character could easily get ganked if the dice rolled the right way.

 

[GMMichael]

As an example, take a gander at the Hobgoblin, a critter that came up enough to matter in my run. I'm going to post the comparisons directly beside one another like so [3e | 5e].

AC 15 (+1 Dex, +3 studded leather, +1 light shield) | AC 18 (chain mail [16], shield [+2])

HP 1d8+2 (6 average) | HP 2d8+2 (11 average)

Attack: Longsword +2 melee (1d8+1) or javelin +2 (1d6+1) | longsword +3 (1d8+1 or 1d10+1 if 2-handed) or longbow +3 (1d8+1) PLUS 2d6 for 'sneak attack' if target is engaged with an ally

CR: 1/2 | 1/2

This comparison is missing something important: there are no labels for the 1/2s. And what's missing is "1/2 party level of 3e characters" and "1/2 party level of 5e characters." My hope, and I saw some agreement, is that these are two different things.

What DMs are going to have to figure out is that just because a party bumrushes a pair of hobgobs and they die in a single round, doesn't mean that he can start throwing more and more hobs at them and expect the same mopping up result, or just 'some damage spread to everyone'. Because while the odds of an insta-kill are longer with only two... they grow more and more for each additional hob you throw into the mix. And that "Hard" encounter designation is there to tell us that. The entire party might not take a pounding, but a single character could easily get ganked if the dice rolled the right way.

Ah, the joys of quantifying the unquantifiable. I hope lots of DMs read this and take heed. And I'm wondering: are 5e's challenge ratings based only on -killing ability-?

I get the feeling a lot of the discussion about 5E, especially about character balance, is still rooted in 3E assumptions - taking it for granted that spells work the same way, for example.

That would be one consequence of releasing version 3.8, instead of 5. I'm going to sound like a broken record, but maybe we can wait until we actually read the 5e DMG before getting worked up?

 

[77IM]

The Challenge 1/2 means that two of them should be a hard encounter for a level 1 party of 4 PCs...

Where does it say this? I can't find anything indicating this, and the monster XP math (catchy tune, btw) does not seem to bear this out, although it comes close at low levels. Everything in the book about CR just uses it as a comparison to the average party level.

I would love for this "total CR = party level" to be true, because it would make encounter building easier, but it implies that two CR 8 monsters are a hard challenge for a level 16 party of four, and that's clearly false.

 

[jadrax]

Where does it say this? I can't find anything indicating this, and the monster XP math (catchy tune, btw) does not seem to bear this out, although it comes close at low levels. Everything in the book about CR just uses it as a comparison to the average party level.

A monster’s challenge rating tells you how great a threat the monster is. An appropriately equipped and well-rested party of four adventurers should be able to defeat a monster that has a challenge rating equal to its level without suffering any deaths. - basic DM's Guide 0.1, page 5.

I would love for this "total CR = party level" to be true, because it would make encounter building easier, but it implies that two CR 8 monsters are a hard challenge for a level 16 party of four, and that's clearly false.

It does not imply that. I know that is how it worked in 3.5, but its not how it works in 5th. A Challenge 16 monster is a hard challenge for a level 16 party of four. Two Challenge 8 creatures is actually equivalent to a Challenge 11 creature, and two Challenge 11 creatures is equivalent to a Challenge 16 creature. It is not a liner progression like in 3.5.

 

[I'm A Banana]

5e's quicker combats come, in part, from a higher damage:hp ratio. You kill monsters in 2-3 hits, they kill you in about the same (or one hit in the right circumstances! .