D&D 5E Encounter Building math: or I killed 2 PCs last night.

[Tormyr]

Ogres don't really have ways of charging through back lines unless it's a wide open field (ie, the PCs have not controlled the fight), nor of coping with mass difficult terrain (such as from spell effects), or status effects.

Sorry, I'm confusing the issue by referring to Body Thief, not Devour Intellect. It's probably true that it's better for other creatures that stun, like mind flayers, to keep around (to turn stunned into dead), but hey, mass attempts can still be pretty effective.


Yep, that's why I said they didn't playtest any of these things widely. A group here or there, absolutely, but hardly enough that I'd have faith in anything over level 6 or so being robust. The XP guidelines in particular the multiply for extra creatures I'm not sure saw any playtest by anyone, in any way. They are a theorycraft construct used for theorycrafting what might be reasonable for your group. They can get it right sometimes, but there's no rigor involved.

With their low intelligence, I see ogres taking simple orders or employing brutish tactics. I could see them trying to knock down defenders holding a line through numbers or knocking the front line defenders down and trampling them or any number of things that could work for a bunch of angry, club-swinging guys. I think I was more going for, "I don't see a huge amount of difference in the deadliness of a bunch of CR2 creatures." Whether they are dinos, slimes, large animals, NPCs, gricks, gargoyles, griffons, or whatever. The tactics to deal with them will change a bit, but the danger to the party is roughly the same.

Of course, putting a CR7 creature (the mind flayer) in the fight dramatically ramps up the difficulty, but the encounter is more dangerous because of the mind flayer, not that the intellect devourer has a mind flayer with it (I think there is a subtle difference there). In this case I could see the encounter difficulty reasonably being (450 + 2900) * 1.5 = 5025. More than the 1350 of two IDs or the 3350 without the multiplier but less than two mind flayers at 11600. I also think this would be appropriate with a different CR2 creature with the mind flayer. The mind flayer stuns, and a big bruiser gets to attack with advantage for lots of damage.

While an open playtest would have been nice, it easily could have taken another year for how many creatures they had. I am content if they have good rules for building creatures and make those guidelines available to us. So far, every creature I have used off the shelf has worked quite well.

 

[travathian]

I have no idea how the PCs survived the encounter in the OP. Short of having surprise, perfect tactics, and incredibly lucky rolls it should have been a wipe.

 

[travathian]

If the intellect devourer was at 575XP, It would be hard for the level 2 party of 4 and 2 of them would still be deadly, but is an intellect devourer really hard for the level 2 party? It has lousy AC and low hit points for a CR2 creature, on par with a CR2 wizard. The party of 4 is going to take it down in 1 round, and the creature will be fortunate to get 1 shot off.

And this is why it is a poor example for discussing CR/XP. An intellect devourer isn't just going to be standing there waiting for the party to show up, then leap up at one of them to attack. Duh, of course it would get squished. The reason for its CR is not due to its AC/HP/Atk, it is due to its special abilities. A lone ID in a dungeon would be hiding, stalking, seeing if a PC is dumb enough to go off on its own,waiting for an opportunity to attack.

Even with two of the IDs, they still would not attack a full party of PCs on open ground in a full frontal assault.

If we want to use Intellect Devourers at the full potential of the CR . . .

The party stops by the inn of a small town after a long day's march. The townsfolk cheer the arrival of adventurers and speak of a nearby group of <insert monster> that has been bothering the town. The kindly innkeeper/bartender offers the PCs each their own room and all they can eat and drink tonight as incentive to help out the town tomorrow. At least a couple of the PCs get rip-roaring drunk and pass out in the bar, only to be carried up to their rooms by their fellow adventurers. The now incapacitated PCs become victims to Body Thief by the innskeeper and the bar wench, leaving the 2-3 remaining PCs to fight against their once allies.

Tell me again how that is not 'beyond deadly' to a party of 2nd level PCs?

 

[Tormyr]

And this is why it is a poor example for discussing CR/XP. An intellect devourer isn't just going to be standing there waiting for the party to show up, then leap up at one of them to attack. Duh, of course it would get squished. The reason for its CR is not due to its AC/HP/Atk, it is due to its special abilities. A lone ID in a dungeon would be hiding, stalking, seeing if a PC is dumb enough to go off on its own,waiting for an opportunity to attack.

Even with two of the IDs, they still would not attack a full party of PCs on open ground in a full frontal assault.

If we want to use Intellect Devourers at the full potential of the CR . . .

The party stops by the inn of a small town after a long day's march. The townsfolk cheer the arrival of adventurers and speak of a nearby group of <insert monster> that has been bothering the town. The kindly innkeeper/bartender offers the PCs each their own room and all they can eat and drink tonight as incentive to help out the town tomorrow. At least a couple of the PCs get rip-roaring drunk and pass out in the bar, only to be carried up to their rooms by their fellow adventurers. The now incapacitated PCs become victims to Body Thief by the innskeeper and the bar wench, leaving the 2-3 remaining PCs to fight against their once allies.

Tell me again how that is not 'beyond deadly' to a party of 2nd level PCs?

Sure, but AC, hit dice, damage and abilities are how CR is calculated. Of course if the ID is on its own it will be sneaking about, but a level 2 party will have around a 50% or slightly better chance of detecting it with passive perception.

In the scenario given, any set of CR2 assassins has the potential to kill off a couple of the inebriated party. In most scenarios, there are clues that there is something amiss. The PCs would have a chance to find out what is going on, and failure or willfully ignoring the clues would lead to the scenario presented.

Even if the party drinks themselves to the point where they have the poisoned condition, they do not have disadvantage on saving throws. The IDs have to sneak into the PCs locked room, and attack a PC. The ID has to get out of its host body which will die in one round. The ID has to decide whether to use devour intellect first or body thief directly. If devour intellect is used, the PCs have to fail their Int save and have the ID roll higher than their int score on 3d6. Then the ID has a significant advantage on the Int contest. If Body Thief is used directly, the ID has no advantage in the contest unless the DM rules that the poisoned condition is still active and gives the PC disadvantage in the Int contest.

Is it dangerous? Sure. Is it more dangerous than another set of CR2 assassins (because in this scenario, that is what the IDs are)? Not particularly. Is it more creepy with IDs doing the invasion of the body snatchers thing? Definitely.

 

[aramis erak]

Except their "just multiply the whole thing by a bunch as you add more" theory is really awful. It's the opposite of what you should do for monsters without synergies, especially melee-centric ones who will have difficulty bringing their might to bear and are easily taken down by AE, and the math/break points on it are silly.

On the other hand, some monsters have extraordinary synergies that could just be called out.

One monster with 2 attacks, and 20 HP is axiomatically worse than 2 monsters with 1 attack each and 10 HP each.
All monsters have synergy of numbers, simply due to 3 goons having more flexibility than one goon.

Some have additional synergistic effects due to powers, sure, but 3 townsmen at once is still a fair sight stronger than 3 townsmen one after the other. And the same is true of EVERY monster that doesn't kill it's "allies."

 

[keterys]

One monster with 2 attacks, and 20 HP is axiomatically worse than 2 monsters with 1 attack each and 10 HP each.

That actually often isn't true.

If your party deals 10 damage per round, then the single monster gets off 4 attacks before it dies, whereas the two monsters get off 3.

If your party has _any_ area effect in it, even down to a simple burning hands spell, then a single attack can take out the two 10 HP people whereas it cannot take out the single high HP target.

All monsters have synergy of numbers, simply due to 3 goons having more flexibility than one goon.

As well as limitations - for example, when presented with the classic D&D chokepoint of a 5-ft. wide corridor or doorway, 3 goons is far less effective than 1 that is three times as powerful.

Now, more creatures do have advantages against single target spells and conditions, there's the possibility of blow-through (though it's fairly rare in 5E compared to many other editions), ability to overwhelm reactions, all kinds of things - but it's not automatic.

Some have additional synergistic effects due to powers, sure, but 3 townsmen at once is still a fair sight stronger than 3 townsmen one after the other.

This is true, but one ogre who is three times as tough and hits three times as hard is often far scarier in D&D terms, which would be the far more accurate comparison.

 

[wedgeski]

Except their "just multiply the whole thing by a bunch as you add more" theory is really awful. It's the opposite of what you should do for monsters without synergies, especially melee-centric ones who will have difficulty bringing their might to bear and are easily taken down by AE, and the math/break points on it are silly.

The "opposite"..? You're suggesting that there comes a point where adding melee-focused monsters makes an encounter easier? That they'll just crowd-around a PC like a game of Diablo, squeezing as many of themselves into fireball radius as they can?

On the other hand, some monsters have extraordinary synergies that could just be called out. Intellect Devourer could be double xp when grouped with a monster that incapacitates (stuns), triple xp when grouped with other intellect devourers. Now DMs won't be surprised when one intellect devourer sets up the other to automatically devour the brain of a PC. And it's not like the math is fiddlier than what we have (which is pretty awful). Hobgoblins have synergy with, well, everything, so are pretty crappy XP on their own, but great XP as soon as you add any number of melee-capable allies.

This is what the DM is for. Encounter building spreadsheets can only take you so far.

P.S. The really sad thing about the intellect devourer example is that it doesn't really get much easier as you level. It's not like your save bonus goes up much, so running into 10-20 of them at high level? Better not be surprised, win initiative, and hope you can kill almost all of them before they go.

Why is that "sad"..? This is a good thing. A higher-level party may not bring much better ability scores, but it will bring better preparation, better magical defenses, better recovery, better everything.

 

[keterys]

The "opposite"..? You're suggesting that there comes a point where adding melee-focused monsters makes an encounter easier? That they'll just crowd-around a PC like a game of Diablo, squeezing as many of themselves into fireball radius as they can?

Not easier, no. Diminishing returns, absolutely.

It is very easy for hordes of melee-centric monsters to die without getting in an effective attack. If you haven't done higher level 5E (or every other E of D&D, really) and seen what happens when 40 very weak foes meet a party with the appropriate resources, then I assure you that the difference between 30 and 40 was not 1/3 more effective, or even 1/6 more effective. It was just a question of mop-up vs. not. This isn't just a question of fireballs, either - a defensive fighter with heavy armor mastery holding a chokepoint can be a heck of a thing, too.

 

[Sword of Spirit]

I really hope they find a way to fix that table for multiplying the effective XP value for more than one opponent. That extra measure of complexity (they even call it a "complex" vs. "simple" encounter!) is going to discourage many DMs from using multiple opponents, and we'll end up with a lot of single creature fights, just because they don't want to mess with it. That's one thing that bugged me about 3e--figuring out how to balance fights with multiple creatures was a real pain.

Months ago Mike had an article saying that the plan at the time was more along the lines of "if the monsters outnumber the PCs by 2 to 1...if they outnumber them by 3 to 1..." I would much rather have something simple like that where a DM doesn't even have to think about it until the monsters outnumber the PCs.

This whole mess where an extra step gets added on as soon as you have more than one opponent is not an encouragement for interesting and varied encounter building.

 

[RangerWickett]

The first combat I ran in 5e was three 2nd-level PCs vs. one skeleton.

The second combat was five 2nd-level PCs vs. an orc, a mastiff, and a death dog.

The third was the five 2nd-level PCs and 5 4-hp townsfolk who they had armed with spears, standing atop low mesa with only one path to the top, in the rain, at night, against 10 orcs, a 1st level orc wizard, two mastiffs, and an ogre.

That was probably the most epic low-level fight I've ever witnessed. With a bit of time to set up, they hid a bear trap in the trail, which took out one of the mastiffs. A sleep spell knocked out most of the townsfolk. Two PCs in armor held the front line while a mother (whose baby was crying in the background) attacked past them with a spear. Two PC warlocks and a crossbowman used boulders for cover while attacking from afar. The ogre ordered some of the orcs to peel off and try to climb the side of the mesa, so the PCs ordered the mom to quickly wake the other townsfolk.

One PC went down, but got healed back up, and while he was lying face down in the mud beside a still twitching orc corpse, he had the idea to use the orc bodies as weapons. The townsfolk dragged the corpses away from where the two armored PCs were holding the line, and they rolled them down the sides of the mesa, knocking loose climbing orcs. The orc wizard reached the top and cast burning hands at a mass of townsfolk, but the rain must have reduced the spell's effectiveness (he rolled low), and none of the townsfolk fell. Not wanting to give the orc another try, one PC fighter broke off from the front line and just hurled the bastard off the top of the cliff.

The ogre finally reached the top of the trail and started to wallop PCs. Warlocks cast curses at him, crossbow bolts peppered him, the paladin smote him, and finally he went down. The three orcs who were still trying to climb the rainslick side of the mesa realized they were outmatched and fled into the night.