Encounter/CR Rules An Artform

Zardnaar

Hero
A lot if people on the forums seem to think the encounter rules are not very good.

Personally I barely use them but I thought I would take a look.

One big mistake I see is people looking at CR numbers and thinking CR= level. Or they think in terms of 3.5 with CR being +/- 4.

Even in 5E this is blatantly false. For example using Hoard of the Dragon Queen as an example at level 7 you can encounter a CR13 white Dragon. Totally unfair right?

A white dragon is worth 10000 xp so going to page 82 of the DMG a deadly encounter for 5 level PCs is 8500xp for a party of 5 or 10200xp for 6 PCs. That dragon is a bit if a stinker encounter RAW for 5 PCs at level 7 but perfectly fine RAW for 6 or 5 PCs at level 8.

Deadly encounters in 5E also don't tend to be that deadly but if you deplete the PCs resources over the 6-8 expected encounters that dragon will probably start to look a lot more dangerous. RAW are working as intended?

I suspect a lot of people are running less than the 6-8 encounters however and outside a dungeon hack it's probably harder to justify at least from a narrative in game world. For example an urban adventure probably won't have that many encounters nor will a hex crawl. And if they do you have probably found a dungeon in the city.

Now the example I used a dragon. Action economy doesn't tend to favor big solo type critters regardless of how big they are. Unless the CR is quite higher than the PCs.

Now looking at that deadly xp budget for level 7 PCs again. 10200xp. That budget is enough for almost 15 CR 3 critters each worth 700xp. However there is multiplier for numbers on page 82. 3-6 of them have a X2 multiplier.

6 CR 3 critters are worth 4200xp but are treated as 8400xp which is roughly a hard or deadly encounter.

How tough that encounter is would depend on what the CR3 critters are. Alot of NPCs are CR3 such as knights, veterens archers along with spellcasters in Princes of the Apocalypse.

An NPC party could be a knight, Archer, 2 veterens and 2 spellcasters. A decent looking fight but probably not in the same league as the Dragon.

However what if you use 6 hellhounds instead? A pack of 6 hellhounds can pump out 36d6 damage worth of breath weapons.

CR 3 is also when NPC spellcasters turn up with level 3 spells. This includes fireball and lightning bolts. This boosts up damage to 48d6 and spells don't need to recharge.

So right there we have 3 examples of how extreme 5E encounter rules can be RAW.

Compounding that is what the PCsare playing.

6 PCs no feats
6 PCs feats
6 newbs
6 powergamers
6 experienced players.

And this ignore party composition, terrain, positioning, cover etc. Do you have 2-4 primary casters? How much healing is available.

This is why I think encounter guidelines don't work. Even new players can struggle and some if these deadly encounters are not that deadly. Others are rapidly heading into tpk area.

Personally I have switched to using milestone leveling. They get to level up if they defeat Bob. They can hack their way to Bob, lure him out, or sneak up to him avoiding encounters. They can also defeat Bob socially either by talking Bob around/down or possibly going over Bob's head to Bobs superiors.

My deadly encounters are also around 50% to 100% above the party level in terms of CR. The higher level the PCs are the larger that gap can be. I don't use the multiplier for mooks so a dragon might have a dozen or two Kobolds helping them out especially if the PCs are level 8 or 9.

5E critters also deal lots of damage relative to CR. Spellcasters also have a high level relative to CR with level 18 casters starting around CR 12 which means PCs around level 6 or 7 can start encountering them.

How dangerous those spellcasters are depends on what spells they are packing. This is an old trick dating back to AD&D which might have something similar but they won't have the best battle spells memorized. RAW meteor swarm level 7 is fine.

Now don't get me wrong this is not a shot at 5E the rules weren't any better or worse in 3E or 4E. AD&D 2E gave more vague oultines but covered basics such as don't use critters that require magic weapons to hit if more than half the party lack them.

Personally I mix things up. One session won't have any combat or 1-2 encounters, next session all combat one after that 2-4 encounters. My last one had undead hordes my latest dungeon for level 5 PCs includes lots of constructs in the CR 7-9 range. A deadly+ encounter in my games can go X5 over the deadly xp budget often for a boss fight with 1 encounter/day.

Ymmv of course. However you do it have fun.
 
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cmad1977

Adventurer
My experience with the CR rules have been really positive. They are NOT hard and fast rules. They do seem to largely deliver what they promise.

One example:
I designed the final session of ToD using the CR rules.
The final fight, by CR, was a medium encounter. With that in mind, after the heroes had chosen their approach to the still rising Temple of Tiamat, I chose to have the following spread of encounter difficulty.
Medium
Hard(with help)
Deadly
Medium(the final scene in the temple with the cultists summoning Tiamat).

It turned into a white knuckle race to stop the ritual (2 rounds left).

In context the CR rules work great. Especially when there are more than just combats that challenge the players or when the fights involve objectives that aren’t simply “smack the bad guys”

IME of course.

PS: I also don’t get butthurt when one of my ‘deadly’ encounters gets negated by clever play.

Example:
Had a great swamp scene with these scary beasts (forgot their name) being led by bullywugs. I was looking forward to a great scene of panic as the Things started turning people to stone. The Tenpest cleric caused a massive wave that washes the beasts away and left a bunch of wimpy bullywugs to be slaughtered. Awesome.

But: The tempest cleric had used one of his few high level slots and other powers were used in the fight so... I feel the CR rules still kinda delivered.
 
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Oofta

Title? I don't need no stinkin' title.
Deadly doesn't mean auto TPK, it just means there's a good chance of killing a PC. In addition, there's no one formula that will work for every group. I've run for multiple groups at the same time, same level, same options. Yet one group could handle significantly tougher encounters.

In any case I use alternate spreadsheet that works fairly well. Basically it just adds up the XP budget for both sides and compares while ignoring the number of opponents. I'd attach the document, but apparently you can't attach spreadsheets on this board.
 

Zardnaar

Hero
Deadly doesn't mean auto TPK, it just means there's a good chance of killing a PC. In addition, there's no one formula that will work for every group. I've run for multiple groups at the same time, same level, same options. Yet one group could handle significantly tougher encounters.

In any case I use alternate spreadsheet that works fairly well. Basically it just adds up the XP budget for both sides and compares while ignoring the number of opponents. I'd attach the document, but apparently you can't attach spreadsheets on this board.
Yeah ignoring the number multiplier is usually a good idea unless they have a AoE effect or can cast spells.
 

Oofta

Title? I don't need no stinkin' title.
Yeah ignoring the number multiplier is usually a good idea unless they have a AoE effect or can cast spells.
Aww, c'mon. There's nothing wrong with throwing a half dozen flameskulls (they're only level 4!) at a level nine party and then setting up the scenario so that there's a good chance they all go first. Oh and monsters always go on the same initiative, right? My wife would never do that! :rolleyes:

So yeah, even with a guideline that works 80% of the time, you still need to take into consideration environment, spells, how worn out the party could be and so on.
 

tetrasodium

Explorer
in 5e, the CR rules & multiplier thing in the dmg is pretty useless due to being overly complex & fiddly in practice... but the table in xge giving rough estimates is useful for ballparking it.
 
I agree. Encounter building is largely a creative endeavor.

However, an aspect of the conversation that's often overlooked is the Adventuring Day Adjusted XP Budget on DMG page 84. Those adventuring day guidelines are actually a decent starting point, in my experience.

So in your example – four 7th-level PCs (adventuring day adjusted XP = 20,000) against a CR 13 adult white dragon (XP 10,000) – it's definitely a winnable yet challenging fight for a party that's fresh, playing smart together, and/or well-prepared for a flying frost-breathing monster.

I actually ran an encounter quite similar to this with a party of four 6th-level PCs (adventuring day adjusted XP = 16,000) fighting a CR 12 titanoboa (XP 8,400). It played as very tense, with some close calls, one PC death averted by the luck of the dice, but ultimately the PCs won and cut the head off the snake. There were no combat encounters prior to this one during that adventuring day, though they did expend some resources exploring. Later in the same session they encountered another enormous snake, though this one was blind and they parlayed with it. The players were very nervous about the prospect of fighting another enemy as tough as the titanoboa they slew, but fortunately their parlay went over smoothly. Having that fight before the parlay helped build tension during the interaction scene.
 

Zardnaar

Hero
I agree. Encounter building is largely a creative endeavor.

However, an aspect of the conversation that's often overlooked is the Adventuring Day Adjusted XP Budget on DMG page 84. Those adventuring day guidelines are actually a decent starting point, in my experience.

So in your example – four 7th-level PCs (adventuring day adjusted XP = 20,000) against a CR 13 adult white dragon (XP 10,000) – it's definitely a winnable yet challenging fight for a party that's fresh, playing smart together, and/or well-prepared for a flying frost-breathing monster.

I actually ran an encounter quite similar to this with a party of four 6th-level PCs (adventuring day adjusted XP = 16,000) fighting a CR 12 titanoboa (XP 8,400). It played as very tense, with some close calls, one PC death averted by the luck of the dice, but ultimately the PCs won and cut the head off the snake. There were no combat encounters prior to this one during that adventuring day, though they did expend some resources exploring. Later in the same session they encountered another enormous snake, though this one was blind and they parlayed with it. The players were very nervous about the prospect of fighting another enemy as tough as the titanoboa they slew, but fortunately their parlay went over smoothly. Having that fight before the parlay helped build tension during the interaction scene.
Funny my PCs are level 5 and I thought about using a titanoboa but thought it was a bit cruel. Leave that idea to level 6 or 7.

I'm using Possessed Pillars and Ushtabi from the same book inside a magical egg dungeon where the top is a magical electrical storm. To get to the other rooms they have to climb over the walls exposing themselves to the storm.
 

Shiroiken

Adventurer
I've ignored the Encounter Guidelines since I started running 5E. Since I was converting 1E adventures, I just ran with what was there, and my players were fairly experienced with D&D (if not necessarily 5E, even though we all did the playtest). I started checking some of my "encounters" (I hate this term, because I design for what should exist, not what the party can handle), and found that they were regularly taking on twice the Deadly value, even disregarding the multiplier for number of creatures. I've even hit them with triple Deadly, but one Hard encounter with them at nearly full resources was almost a TPK because the party wasn't properly prepared.

Parties vary in player skill, cohesion, and tactics, and no single system is going to work for everyone. The problem with 5E is that these are simple guidelines that can be easily broken in either direction. Two Adult White Dragons can be only a Hard encounter for a high level party, but if the party isn't prepared correctly, it can be vicious. Conversely a horde of orcs might be Deadly for the same group, but with enough AoE and some distance, it's a cakewalk.
 

Oofta

Title? I don't need no stinkin' title.
Threads like this make me remember how much I miss the 4e monster math.
I find it odd that people have such difficulty. Once I found the alternative spreadsheet (similar to the guide in XGTE) it's worked pretty well.

It takes a bit of trial and error to figure out what works because every group is different, but once I dialed it in it's been quite accurate. Then again I tend to have 5-10 encounters between long rest, people rarely have much prep time and I use environment and tactics to the monster's benefit.

But even if the group stomped on all the encounters it would just mean I need to up my XP budget.
 

DEFCON 1

Legend
My inclination is to say the Challenge Rating and encounter building rules have been set up to be relatively balanced only against a 4-person party using the Basic Rules. Basically a new-player game.

Thus probably only one character to heal others, one character to put out AoE with any possible consistency, no feats, many fewer classes that reduce the possibility of good class synergy, and many fewer PCs to reduce the number of hit points and actions to be taken in a round.

You change any of these things and the power of the party begins growing exponentially. More PCs means maintaining steady damage against monsters even when some are using action to heal others. More PCs on their feet means more hit points for monster to have to churn their way through and less actions available to do so against them. More varied classes and using feats means more opportunities for mixing and matching powers and features and spells together to maximize effectiveness-- gaining more opportunities for Advantage, more AoE damage, more blockers and defenders to keep enemies away from the PCs in the back lines.

Has anyone actually ever run a new-player-friendly Basic Rules game with only 4 PCs? And did you design encounters using CR and the builder rules? If so, did they actually work as-is or did you still have to fuzt with it?
 

Celebrim

Legend
I think CR has been a step forward from the much vaguer situations in 1e or 2e, but it should not be treated as a hard and fast rule. In other words, I fully agree with you that producing fair and interesting challenges still remains more of an art than a science.

The following always remains true:

1) CR is often wrong. Assigning CR in the first place is an artform, and it's often wrong in published material by +/-1 or in some cases even +/-2.

2) Even when CR is not wrong, the range covered by a single CR is fairly large. If you take any arbitrary number, say CR 5, you will be able to find some monsters that are CR 5 which are almost but not quite CR 4 and others which are almost but not quite CR 6. That means within the same CR range you can have monsters which are 150% or more as deadly as other monsters with the same CR. Similarly, if you are RBDM, you know that you can make small tweaks to a monster that are insufficient to alter it's CR but which make it 10% or 20% more effective. A good example is a default Ogre has primitive weapons like a club and makeshift hide armor. But an ogre working as a mercenary might have a two-handed sword and mail. That change makes the Ogre much more dangerous, but not so much more dangerous that it bumps it up a full CR.

3) Every campaign and every party is different in its assumptions and in its composition, and as such different challenges will be of different difficulty to different groups. Some parties I've had were tightly focused on melee combat, and anything that they could close with and surround would get beat down quickly. Other parties I've had focused on battlefield control and ranged combat, and anything that couldn't close quickly with them would be easily dispatched. Those two parties will have very different challenges with a burrowing ambush predator that achieves surprise. Likewise, I've had a party focused on undead slaying that could handle masses of undead that would have been lethal to a different party composition of the same level.

4) CR never takes into account tactics. In particular, the terrain that a fight takes place in massively alters the effective CR of something. If the monster is fighting in its favored terrain and circumstances, it will tend to be massively more dangerous than when it is not. As a very simple even comical example, a giant shark is a very different encounter when encountered on land, encountered in a boat, and encountered when the party is in the drink with it. The effective CR of a monster depends a lot on the lair the DM designs for that monster, and double or half the encounter difficulty all by itself. Any lair that the monster can make better use of than the party is a massive advantage that should be accounted for but often isn't. Coming from the opposite direction, challenge rating almost always assumes that the party will adopt the most effective tactics to counter and defeat a monster. But if the party doesn't understand the weakness of what they are facing or adopts the wrong strategy, the challenge can go up enormously. That party that is good at surrounding things and beat them down, if they adopt that strategy against a monster whose CR is based on the assumption the monster can and should be kited, will massively up the lethality of the monster.

5) CR never takes into account synergy. Synergy happens when two monsters are more than the sum of their parts, because each is able to cover for the others weakness. For example, a troll and spellcaster working together are more dangerous than either alone, because the spellcaster can give the troll resistance to fire while the troll can tank for the spellcaster and use it's reach to provide battlefield control. Synergy also happens when you alter an existing monster in a way that the rules for altering a monster consider to normally be minor, but which in this particular case cover up for a monsters weakness tremendously. An example might be a small or medium sized grappler tends to have low CR on account of the weakness of its main attack - grappling. Normally increasing a monster by a size category has only a minor increase in its effective CR, but increasing a small or medium sized grappler by a size category tends to have synergy and increases CR by more than the normal degree.
 

Celebrim

Legend
Threads like this make me remember how much I miss the 4e monster math.
4e went all in on making encounters be balanced and predictable, and yet it has many of the same problems.

4e math assumes that the party will be balanced and equally divided between the 4 interchangeable party roles.

4e math assumes that the encounter will take place in a relatively small "arena" which is at a scale wherein the powers and move capabilities of both sides are highlighted.

And so forth. And that's to not even get to the fact that the initial math that they used generated monsters that were generally too weak at higher levels to seriously threaten a compotent and well built PC party.
 

Oofta

Title? I don't need no stinkin' title.
Another quick note on CR: the original monster manual was released before the DMG and the final rules for how to determine CR were still being finalized. I find that monsters created after the DMG was created are a little closer.

However, there is still no way that CR will ever be more than a general guideline. One group may have high overall ACs but poor dexterity saves for example. So those hell hounds, whose CR is based in large part on their breath weapons, will be more effective against some groups than others. Doubly so if the group has time to prep.

I remember way back when having a conversation with one of the WOTC devs working on 3E* how hard it was as a DM building encounters or custom monsters for 2E. No real guidelines, just take a gander at the monsters and hope for the best. No guidelines for XP for custom monsters. I had my own crude guidelines taking into consideration damage, AC, HP but nothing as comprehensive as what we had now. Most of the time we just winged it.

Which is all to say the current guidelines are far from perfect, but I find they still work fairly well. I still have to take into consideration a bunch of variables that can't be put into a spreadsheet. D&D isn't a board game with identical pieces, it's the best we can hope for.

*My brother-in-law lives in Seattle and he won a charity contest to play with a dev at WOTC HQ not that long after they'd bought TSR. It was quite fun even though my PC died a valiant death.
 

5ekyu

Adventurer
It has seemed to me that the CR DMG was scaled for the assumption of "relative novice of systrm" and " low to average tactical savvy" with a lot of wiggle room. Thst seems good to me to prevent the slaughtered-newbie-walks before they get a handle on things.

For groups who know enough to optimize, to use savvy tactics etc its expected the GM knows to adjust.

BTW what are golks views on the XGtE alternative encounter balancing?
 

tetrasodium

Explorer
It has seemed to me that the CR DMG was scaled for the assumption of "relative novice of systrm" and " low to average tactical savvy" with a lot of wiggle room. Thst seems good to me to prevent the slaughtered-newbie-walks before they get a handle on things.

For groups who know enough to optimize, to use savvy tactics etc its expected the GM knows to adjust.

BTW what are golks views on the XGtE alternative encounter balancing?
the xge charts are a pretty decent ballpark tool, the game being "balanced" around a style of play nobody uses is probably a big part of why the dmg calculations are kinda useless compared to prior editions, Celebrim touched on that style above
 

robus

Lowcountry Low Roller
As @Quickleaf notes, the CR is only relevant if the PCs are going to be sufficiently challenged over the course of an adventuring day. If they can nova the only encounter of the day then yeah, unless the monster gets some lucky rolls/high initiative it's not going to provide a sufficient challenge. Now that my players are at level 19 I've completely thrown out the guidelines and just throw whatever seems thematically appropriate for the adventure at hand :) - But I'll generally boost monsters with attack bonuses (if they seem low) and more HP to make the fight more challenging.

Someone also had the great suggestion of forgoing initiative rolls for monsters, just use a fixed initiative: dumb monsters 10, smart monsters 15 and bosses 20 (given that I rolled a 2 for some monsters initiative - in a low level game - I'm especially partial to this idea :) )

As for the tables in Xanathar's guide, I think they're great for low level encounter planning.
 
I think CR has been a step forward from the much vaguer situations in 1e or 2e, but it should not be treated as a hard and fast rule.
That's fair, and very well-chosen, because it is a step forward from those editions. And a lateral move from 3e, and a big step back from 4e.
Which is so frequently the case with everything 5e has done as a Compromise/Big-Tent edition trying to pull the high points from each prior ed, that we really should be used to accepting it, by now, 5 years in. ;)

I mean, 3e introduced CR, and 4e improved on it substantially, but 5e, had to call back the TSR eds, as well. It couldn't make encounter building into a detailed optimization mini-game counter to the players build-optimization mini-game like in 3e, or a neatly-balanced exercise in set-piece combat 'scene' choreography like 4e. It had to bring us some of the uncertainty and DM/player 'skill' of the olden days, too.

In other words, I fully agree with you that producing fair and interesting challenges still remains more of an art than a science.
It is, indeed, once a gain, primarily an art - a matter of feel, experience, improvisation, and creativity. Which is both a good deal of fun, and takes a good deal of skill/talent/energy to get the most of out of.

So, yes, the following are, once again, true, and advisedly/intentionally so:

1) CR is often wrong. Assigning CR in the first place is an artform, and it's often wrong in published material by +/-1 or in some cases even +/-2.
'Wrong' is the er, wrong? word for it. YYMV, maybe? CRs in published materials seem to follow a formula, that formula, thanks to BA, doesn't stand up to the linear-distribution randomness of the d20, nor party composition nor optimization, since balance on the player side is also far more varied for similar reasons.

2) Even when CR is not wrong, the range covered by a single CR is fairly large.
It maps to level, still. While BA means a party can functionally engage CRs far above and below them, it's still centered around a lone same-CR critter as a meaningful little challenge.

3) Every campaign and every party is different in its assumptions and in its composition, and as such different challenges will be of different difficulty to different groups.
Yes choice of class, build choices, pacing, and many other factors radically distort balance among classes and vs encounters. It's inevitable given the mandates of 5e design. You simply can't give some classed no meaningful daily resources, and others game-changing ones, and give players any freedom in the 'length' of their day and expect any set of encounter guidelines to hold up!

4) CR never takes into account tactics. In particular, the terrain that a fight takes place in massively alters the effective CR of something.
Well, it can, if the DM sets it up that way and runs to that level of granularity.
In this case, though, I think 5e CR deserves a free pass: the game assumes TotM, TotM doesn't support highly granular tactics.

5) CR never takes into account synergy. Synergy happens when two monsters are more than the sum of their parts, because each is able to cover for the others weakness. For example, a troll and spellcaster working together are more dangerous than either alone, because the spellcaster can give the troll resistance to fire while the troll can tank for the spellcaster and use it's reach to provide battlefield control.
And it exists on the players' side of the screen, too!
 

Celebrim

Legend
@Tony Vargas : There seems to be some 4e partisanship going on in your response that makes a ton of assumptions.

For example, with respect to Theater of the Mind, most of the 1e/2e play that I did used TotM as well, but that didn't prevent terrain from having a big impact on the combat situation. Consider just as one of many examples, the terrain challenges poised by a module like S2: White Plume Mountain. Even if 1e didn't have a unified terrain and skill mechanics, terrain minigames specific to an encounter were common in 1e play even in situations where TotM play was assumed. I mean seriously, you wouldn't expect a 1e table accustomed to assume TotM play to nonetheless assume combat continued to function as normal if a Paladin in platemail fell into the salty sea while battling a squid. There would be certainly assumptions made about the ability of the Paladin to move in this new environment - to say nothing of breathing in it. Things like the spell 'Darkness' or just fighting at night creates terrain in 1e even if you are playing in 1e TotM. So I don't think you can say that because 5e assumes TotM that terrain doesn't have a big impact on combat and challenge within it.

As for the assignment of CR, 3e, Pathfinder, and 4e all had monsters which were notorious for being harder than their CR suggested, and which had they been published at the next higher CR probably wouldn't have caused much remark. And as far as I can tell as an outsider, 5e has continued this with several monsters being much harder than their CR would suggest - ropers, magmin, intellect devourers, shadows, zombies, etc. So when I say that the CR is wrong, I mean 'wrong' in a very literal sense that the wrong number was probably assigned to the CR. I mean that even given that all the system expectations were met, the monster in question not only on average outperforms the normal expected amount of party resources consumed, but actually usually forced the expenditure of the sort of resources expected by the next higher CR.
 

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