D&D (2024) 5e 2024 − The Monster Math

[Charlaquin]

I got curious about 2014 vs 2024 encounters, so now that we have the new monster math and encounter guidelines I matched out 2 examples. Thought some people would enjoy it.

2014 Level 10 encounter 4 characters:
Medium Challenge is 4 CR 3 Monsters
Total HP: 240; Total Damage/Round: 80

2024 Level 10 encounter 4 characters:
Medium Challenge is 4 CR 6 Monsters
Total HP: 436; Total Damage/Round: 186

Keep in mind, the suggested XP values for the encounter difficulty breakpoints in the 2014 DMG are floors, while those in the 2024 DMG are ceilings. Which means if your calculations are close to the medium challenge XP value, your 2014 encounter is barely medium and your 2024 encounter is almost hard.

 

[Charlaquin]

It is difficult to make sense of the hit points in the new Monster Manual.

Looking at the average of the official hit points at each CR, the rate of improvement sometimes accelerates, sometimes decelerates, at certain points reverses so the next CR actually has less hit points, and finally at epic CRs (20+) wildly accelerates deviating from any pattern.

The simplest formula to explain the numbers is: hit points = 15(CR+1).

In other words, CR 1 starts at 30 hit points, and after that, each higher CR improves by 15 hit points.

This simple formula closely matches the actual average hit points from CR 1 thru CR 10. Overall, the formula stays true even up to CR 21 where an expected 330 hit points matches the actual 335.8 hit points on average. In the CRs in between, the formula also helps shore up the anemic CRs. For example CR 14 averaging about 200.5 hit points, should instead expect about 225 hit points, which is at least a bit better. CR 17 which averages 254 hit points, should instead be about 270 hit points.

However the simple formula fails to explain the epic CRs. From CR 22 thru 24, the improvement to hit points lurches upward derailing from any formula, improving about 70 hit points per CR on average. Because the epic CRs tend to have fewer monsters, and many of them are unique individuals, it is fair to say the small sampling pool is nonrepresentative of any expected CR. On the other hand, these wildly higher hit points at the upper CRs, might instead suggest, the hit points should have been improving at higher rate all along at every CR.

The Hit Points table below compares the formula, hit points = 15(CR+1), to the actual hit points in the 2024 Monster Manual. Actual hit point averages that are less than the formula by 10% are in red. Actual averages that are more than the formula by 10% are in blue. The formula is solid and helpful, except at the very highest CRs.

View attachment 395012

Most likely because the actual HP values weren’t arrived at by a simple formula. The formula was probably used as a starting point, and precise values were probably further refined through playtesting. That’s at least what they claimed to have done with the 2014 monsters, and there’s no reason to assume they wouldn’t have done the same with the 2024 monsters.

 

[dave2008]

It is difficult to make sense of the hit points in the new Monster Manual.

Looking at the average of the official hit points at each CR, the rate of improvement sometimes accelerates, sometimes decelerates, at certain points reverses so the next CR actually has less hit points, and finally at epic CRs (20+) wildly accelerates deviating from any pattern.

The simplest formula to explain the numbers is: hit points = 15(CR+1).

In other words, CR 1 starts at 30 hit points, and after that, each higher CR improves by 15 hit points.

This simple formula closely matches the actual average hit points from CR 1 thru CR 10. Overall, the formula stays true even up to CR 21 where an expected 330 hit points matches the actual 335.8 hit points on average. In the CRs in between, the formula also helps shore up the anemic CRs. For example CR 14 averaging about 200.5 hit points, should instead expect about 225 hit points, which is at least a bit better. CR 17 which averages 254 hit points, should instead be about 270 hit points.

However the simple formula fails to explain the epic CRs. From CR 22 thru 24, the improvement to hit points lurches upward derailing from any formula, improving about 70 hit points per CR on average. Because the epic CRs tend to have fewer monsters, and many of them are unique individuals, it is fair to say the small sampling pool is nonrepresentative of any expected CR. On the other hand, these wildly higher hit points at the upper CRs, might instead suggest, the hit points should have been improving at higher rate all along at every CR.

The Hit Points table below compares the formula, hit points = 15(CR+1), to the actual hit points in the 2024 Monster Manual. Actual hit point averages that are less than the formula by 10% are in red. Actual averages that are more than the formula by 10% are in blue. The formula is solid and helpful, except at the very highest CRs.

View attachment 395012

It is a mistake to just look at averages and assume it tells the whole piciture. Saving throws, resistances, immunities, and tratis / features all play a roll. I plan on including those in my spreadsheet so we can see why things deviate from the expected values and come up with updated monster creation guidelines.

 

[Scribe]

works for me, 5e monsters were always underperforming at high levels anyway, so that was necessary already, it might no longer be in the future however

Yes, the narrative and for many, played experience was that 5e math was simply flawed. That it's not directly compatible makes complete sense when we look at the power creep of player options.

5.5 is a different game, fundamentally the math makes this obvious.

 

[Charlaquin]

Going back to the level 12 encounter, let's pit a party of 4 12th level characters against 4 critters of equal XP value.

In 5.5 that's very easy. We have 4700 xp per character. That's roughly 4 CR 9 creatures.

In 5e, it's trickier. We have to halve the monsters effective XP to stay within the guidelines, so that leaves us looking for monsters worth 1500 xp each. Ugh! That's roughly 4 CR 5 creatures.

In both cases we're overshooting the mark, but let's see what that gives:

Overshooting the mark using the 2014 guidelines should be perfectly fine, since the mark there is a floor. As long as you don’t exceed the XP value for the next difficulty level up, you’re within the acceptable range. The 2024 DMG on the other hand advises trying to get as close to your intended difficulty’s XP budget as possible without going over, so if you’re overshooting the mark for a Medium encounter, what you have is an encounter that’s on the low end of Hard.

 

[mearls]

Overshooting the mark using the 2014 guidelines should be perfectly fine, since the mark there is a floor. As long as you don’t exceed the XP value for the next difficulty level up, you’re within the acceptable range. The 2024 DMG on the other hand advises trying to get as close to your intended difficulty’s XP budget as possible without going over, so if you’re overshooting the mark for a Medium encounter, what you have is an encounter that’s on the low end of Hard.

Thank you so much for pointing that out! Completely missed it. I have some errands to run, but when I get back I'll do a little more analysis with that in mind.

 

[I'm A Banana]

THANK YOU.

I wonder how these interact with the encounter building rules in Xanathar's. I use those pretty exclusively (since I ain't got time for math, but I can do 1 PC : X Monsters OK!), and I'm a bit concerned about 2024 monsters being too tough given those rules.

 

[mearls]

Let's take a look at the final battle in The Sunless Citadel. Per the module, the characters should be 3rd level when they have this fight.

The NPCs and monsters - Belak, Sir Braford, Sharwyn, the giant frog, and three twig blights - add up to 775 XP.

Under the 5e model, the number of monsters multiplies that to 1900 xp, or a deadly encounter for a 3rd level party of 4 characters.

Under 5.5, 775 XP is a moderate encounter for a 3rd level party of 4. To push it up to high difficulty, we technically need to add 130 XP to exceed the moderate listing, but that doesn't feel right.

I'd expect to aim for 1600 XP for a high difficulty fight, giving us 825 XP to add. We could clone each of the creatures and still be short.

In other words, to make the final fight in a 5e adventure work you need to double the threat or add a CR 3 and a CR 1/2 creature to the fray.

EDIT TO ADD: That also means that Belak is no longer the toughest NPC or creature in the encounter. He's CR 2.

That's wild. I'd expect them to keep the XP and CR values the same, but then make the individual creatures more powerful.

 

[Sulicius]

Let's take a look at the final battle in The Sunless Citadel. Per the module, the characters should be 3rd level when they have this fight.

The NPCs and monsters - Belak, Sir Braford, Sharwyn, the giant frog, and three twig blights - add up to 775 XP.

Under the 5e model, the number of monsters multiplies that to 1900 xp, or a deadly encounter for a 3rd level party of 4 characters.

Under 5.5, 775 XP is a moderate encounter for a 3rd level party of 4. To push it up to high difficulty, we technically need to add 130 XP to exceed the moderate listing, but that doesn't feel right.

I'd expect to aim for 1600 XP for a high difficulty fight, giving us 825 XP to add. We could clone each of the creatures and still be short.

In other words, to make the final fight in a 5e adventure work you need to double the threat or add a CR 3 and a CR 1/2 creature to the fray.

EDIT TO ADD: That also means that Belak is no longer the toughest NPC or creature in the encounter. He's CR 2.

That's wild. I'd expect them to keep the XP and CR values the same, but then make the individual creatures more powerful.

Having run the Sunless Citadel with 3rd level 2024 NPC’s, that tracks. They would have had no trouble defeating double that. Recently I also tested 8 CR 1 lions vs 4 lvl 3 PC’s and it was a perfect high challenge fight.

I wouldn’t use the DMG stats by CR, though. Old monsters are famous for overvaluing defensive abilities and resistances, so that monsters often had a lot less real defense. Unless you don’t give PC’s magic items.

 

[Uni-the-Unicorn!]

Once you see the formula for the expected Attack Bonus, one can plug the numbers in for any CR.

Then your formulas are wrong?