Mixing lower CRs to get a higer CR

[A Ladder]

So, I'm new to DMing and one problem I found was that if I wanted a group of slightly less powerful monsters attacking my party what mix of CR should I go for?

Example: party is level four, I could whip out one big CR 4 creature and have them whack it to death. But if I pulled out 4 CR 1 creatures the party would slaughter the baddies.

What do you guys do to mix and match the CRs? ( if I wanted the party to fight say... four creatures what CR would I choose? if I wanted the creatures to be 2, 3, 6, 8??)

thanks in advance!

edit: Also: Say I wanted to make an assassin bad guy. what level should he be at to give a four/five man party hell without wiping the floor with them?

[Hazzardevil]

4 CR 1 enemys don't make CR 4, theres something on the SRD that helps Calculate CR.
You would need a lot more nemies to make CR 4 encounter

Now the problem with fighting an assasin is that assasins are good at killing a target in one shot and running away.
And PC's don't like dying without a saving throw.
I would say about level 6 to challenge the assasin though in combat.

[Diarmuid]

Page 49 of the DMG has a great table listing what quantities of lower CR's make up a higher CR.

[Eldariel]

Page 49 of the DMG has a great table listing what quantities of lower CR's make up a higher CR.

Though a word of warning: CR is anything but exact science and while these numbers give you a direction, they rarely accurately predict the amount of challenge that group of opponents will present.

Generally, the rule is that two creatures of CR X are equivalent to CR X+2. Then four creatures are CR X+4, eight creatures are CR X+6, sixteen creatures are CR X+8 and so on.


Also note that a party can face creatures above their CR. Indeed, a creature that's an even match for the party would be about CR Level+4; so CR 9 monster for Level 5 party of 4 (again, not an exact science mind but that's the idea behind the CR system).

[Diarmuid]

For the guy self amittedly new to DMing, listed CR's and DMG published patterns for creating encounters is probably a good place to start.

[Tvtyrant]

For the guy self amittedly new to DMing, listed CR's and DMG published patterns for creating encounters is probably a good place to start.

TDC time. Teaching youngsters to hate CR one mistake at a time.

[Eldariel]

For the guy self amittedly new to DMing, listed CR's and DMG published patterns for creating encounters is probably a good place to start.

Aye. One should be careful tho; if something looks to be too strong for its CR, it probably is. That is, don't send a Dragon with CR 4 higher than the party's average level in immediately; that has the makings of a Total Party Kill.

[Morph Bark]

Aye. One should be careful tho; if something looks to be too strong for its CR, it probably is. That is, don't send a Dragon with CR 4 higher than the party's average level in immediately; that has the makings of a Total Party Kill.

Especially if it is from Monster Manual II or Fiend Folio.

[begooler]

I use this (http://www.penpaperpixel.org/tools/d20encountercalculator.htm) and I like it a lot.

[Allanimal]

I use this (http://www.penpaperpixel.org/tools/d20encountercalculator.htm) and I like it a lot.

I second this. This tool is essential for DMs.

[Godskook]

I find that CR is mostly useful for throwing out 'easy' encounters. For the tough stuff, CR is completely out of whack, producing monsters that are either too hard or too easy, regardless of encounter size.

A better way to look at it is to treat it as a study. After each encounter, note some basics about the monsters you threw at them(HP/AC/Saves/Attack/Damage), as well as any mitigating factors of the battle(was a glass cannon or tank disabled?).

A 'combat' should last 3-5 rounds, so after you figure out how much damage per round your party can dish out(30-40 from my boys), you multiply that by the rounds to get the total HP of your group of monsters. For my group, 60 hp of monsters are a weaker challenge, while 120+ is kinda tough to hurt.

For damage, take the PC's HP, and divide by the rounds. My PC's HP is about 20-30 per, and there's 5 of them, so about 120 total. Also, a 'normal' encounter should only tear up 1/4 their HP, so 10 damage per round sounds about right for my PCs. Maybe a little more depending.

For AC/Saves/Attack, a roll of 11 is 'normal', but experience will tell you a lot there too. You also want to avoid both extremes, where only a nat-20 succeeds or a nat-1 fails.

Use the above to kinda eye-ball encounters you're preparing. If what you're sending at the PCs can drop a PC in the first round, and will be able to fight on their terms, that's an incredibly difficult encounter(of rocket tag), while a group of monsters that only hits 1s isn't an encounter, its sword practice.

[0nimaru]

Most of the important stuff has been said, but I'll note one more thing that helped me when I was starting to DM.

CR is based around the theory that the PCs will be fighting four encounters in a day. A CR appropriate fight is actually supposed to be rather easy, and I had some issues finding balance early on when trying to craft proper encounters. It's important to remember that small scratches add up, and a PC taking 10%-15% damage per encounter will have sucked down a lot of healing throughout the day.

Also, at low levels and low CRs. You can almost always add a bit more hp to your monsters. Try to resist the urge to add damage to them though. Combat long enough to let people use their tricks = fun. Insta-gibbed first round because the orc rolled 6x2+X on that greatsword? Feels like time out.

[magic9mushroom]

4 CR 1 enemys don't make CR 4, theres something on the SRD that helps Calculate CR.
You would need a lot more nemies to make CR 4 encounter

Now the problem with fighting an assasin is that assasins are good at killing a target in one shot and running away.
And PC's don't like dying without a saving throw.
I would say about level 6 to challenge the assasin though in combat.

Actually, 4 CR 1s do make a CR 4, by the DMG rules.

Of course, they're an easy challenge for a level 4 party, but so's a CR 4.

[Saph]

I find a good way to get interesting fights is to find a monster that's stronger than its CR indicates but whose CR is a few points lower than the party level, then send a bunch of them at the PCs.

For instance, Orcs (http://www.d20srd.org/srd/monsters/orc.htm) are well known as being extremely nasty for CR 1/2 monsters. Sending a pair of them against a Level 1 party is usually a bad idea, since one critical will put a PC into deep negatives if not dead. However, a group of 8-12 orcs (which the Encounter Calculator (http://www.penpaperpixel.org/tools/d20encountercalculator.htm) will tell you is an EL 4-5 encounter) makes a nice challenge for a 4th-5th level party, especially if you throw in an orc with class levels to lead them.

[Werekat]

That... Seriously depends. I once nearly killed two level 9 characters with 1 or 2 CR 1 monsters.

They were leech swarms in murky water, and the two in question were a Paladin and a Warlock with no spot checks to speak of.

If you're going to use lower CR creatures, see the environment in which they excel, and see if you can get the PCs in that environment - or, on the contrary, if you can get the monsters "out of the water," so to speak, so you can throw more of them in the fray.

[LaughingRogue]

That... Seriously depends. I once nearly killed two level 9 characters with 1 or 2 CR 1 monsters.

They were leech swarms in murky water, and the two in question were a Paladin and a Warlock with no spot checks to speak of.

If you're going to use lower CR creatures, see the environment in which they excel, and see if you can get the PCs in that environment - or, on the contrary, if you can get the monsters "out of the water," so to speak, so you can throw more of them in the fray.

A valid point --- even though it's not taken into account with CR -- terrain comes into account when calculating EL

[Diarmuid]

Actually, 4 CR 1s do make a CR 4, by the DMG rules.

Of course, they're an easy challenge for a level 4 party, but so's a CR 4.

This is actually a bit misleading as 4 CR 1's can range anywhere between EL 3 and EL 5 per the chart.

And taking terrain and favorable conditions is often forgotten about when generating EL. Honestly, I think most DM's just assume that CR = EL.

[Xtomjames]

Here's my take on CR (this is not RAW rules).

When you want to balance an encounter based on CR a simple way to deduce total challenge rating is based on your party. In the DMG there is a rather elaborate way to determine CR versus Party level. I've got a simpler way.

Total CR= number of PCs+PC level-2 (minimum), -1 (middle range) -0 (high range). So for example, if you have a party of four players at level one they should be able to handle a CR 3 creature without much difficulty, CR 4 with a little more difficulty, and CR 5 as the hardest.

If that same four player party is at level 9 it'd be a CR 12 creature minimum, CR 13 middle, CR 14 highest.

For more than one monster the monster's CR should be simply a PC's class level -4. So If you have four 9th level PCs, and you want them to encounter 4 monsters, each monster would be a CR of 5. Two monsters would be a CR of 7.

More monsters than the total group's number, -1 for every two monsters add.

Take the same group of 9th level PCs pit them against 8 monsters, the monsters would have a CR of 3 (max).

For low level campaigns swarms are great for "multiple monsters" but with a single CR. The rules apply above, but presume a minimum CR of 1/2. At levels lower than three never try to pit a group against more monsters than the total number of PCs.

[Diarmuid]

If that works for you, great...and it probably works better at the higher levels, but I would imagine it doesnt work out that great at lower PC levels and/or at lower levels of optimization.

Non optimized level 1's are generally going to get curbstomped by an EL 5.

And again, I'll point out that the OP is an admittedly new DM. He hasnt had time to learn which monsters are fine, OP, or UP so starting with CR as a base and using the intended calculations for mixing up monsters is a great way to start off.

I would imagine your fist DMing session didnt invovle this encounter building formula of yours and that it developed over time.

[Xtomjames]

If that works for you, great...and it probably works better at the higher levels, but I would imagine it doesnt work out that great at lower PC levels and/or at lower levels of optimization.

Non optimized level 1's are generally going to get curbstomped by an EL 5.

And again, I'll point out that the OP is an admittedly new DM. He hasnt had time to learn which monsters are fine, OP, or UP so starting with CR as a base and using the intended calculations for mixing up monsters is a great way to start off.

I would imagine your fist DMing session didnt invovle this encounter building formula of yours and that it developed over time.

You are correct, it did take a bit of time to figure out. But it does work at low levels. A single CR 5 monster against 4 first level characters is the maximum I'd ever put against a class at that level. And also any DM (especially new DMs like the OP) should always consider the skill level of the group when calculating CRs for encounters.


I only offer this method because it is in fact much easier to use than the CR methods provided by the DMG.

[Amphetryon]

I find a good way to get interesting fights is to find a monster that's stronger than its CR indicates but whose CR is a few points lower than the party level, then send a bunch of them at the PCs.

For instance, Orcs (http://www.d20srd.org/srd/monsters/orc.htm) are well known as being extremely nasty for CR 1/2 monsters. Sending a pair of them against a Level 1 party is usually a bad idea, since one critical will put a PC into deep negatives if not dead. However, a group of 8-12 orcs (which the Encounter Calculator (http://www.penpaperpixel.org/tools/d20encountercalculator.htm) will tell you is an EL 4-5 encounter) makes a nice challenge for a 4th-5th level party, especially if you throw in an orc with class levels to lead them.
This approach works better, in my experience, if you give each of the orcs - or whatever substitute monster you're grouping - its own initiative. Done the other way, I've seen far too many encounters where the orcs swarm and destroy the party's tactics before they can deploy, or where the party spams damage on the orcs before they can do anything but show up and hand over the XPs.

[Calimehter]

This approach works better, in my experience, if you give each of the orcs - or whatever substitute monster you're grouping - its own initiative. Done the other way, I've seen far too many encounters where the orcs swarm and destroy the party's tactics before they can deploy, or where the party spams damage on the orcs before they can do anything but show up and hand over the XPs.

I second that. I love giving larger groups of monsters multiple initiative rolls. It adds some complexity to the encounter and almost always lengthens it, but it banishes some 'artificial' strategies that can come from knowing exactly when your enemies are going to act, and from a purely 'mood' perspective it can add some pressure and tension when your opponents are constantly taking actions.

[Gnaeus]

Another important note.

Some monster's CRs reflect that they are essentially trick monsters, where if you use the trick, you win, and otherwise you lose.

For example, big animals. A CR8 Dire tiger has 16 HD. Attacks at +20 to hit, Pounce, decent saves for a CR8. Fighting in melee, dire tigers will likely TPK level appropriate parties.

But the key there is "fighting in melee". No flight. No ranged attacks. very low INT. A level 4 druid on a dire bat with a reserve feat can kill Dire Tigers until he loses his class abilities for killing too many Dire Tigers. At animal intelligence, they are vulnerable to Ray of Stupidity, illusions, or simple tricks like trapped bait.

So, it clearly shouldn't be much higher than CR8, because flight (easily available at level 3-5) crushes them. Shouldn't be lower, because they dominate most ECL 8 meleers. There probably isn't a good default CR for them.

[Flickerdart]

The issue with sending lots of mooks at the party is that the problem of "that one critical" becomes a lot worse when there's more of them rolling the dice - and the squishy Rogue or Wizard doesn't have that many more HPs at level 4 than they did at level 1. Action economy is as important as monster strength when considering a challenge.

[Diarmuid]

Another important note.

Some monster's CRs reflect that they are essentially trick monsters, where if you use the trick, you win, and otherwise you lose.

For example, big animals. A CR8 Dire tiger has 16 HD. Attacks at +20 to hit, Pounce, decent saves for a CR8. Fighting in melee, dire tigers will likely TPK level appropriate parties.

But the key there is "fighting in melee". No flight. No ranged attacks. very low INT. A level 4 druid on a dire bat with a reserve feat can kill Dire Tigers until he loses his class abilities for killing too many Dire Tigers. At animal intelligence, they are vulnerable to Ray of Stupidity, illusions, or simple tricks like trapped bait.

So, it clearly shouldn't be much higher than CR8, because flight (easily available at level 3-5) crushes them. Shouldn't be lower, because they dominate most ECL 8 meleers. There probably isn't a good default CR for them.

Gnaeus, as with many posters here you're also assuming a certain level of optimizations. I would say that not many of the games I've been in has flight been "easy to come by" at levels 3-5. Sure, at level 5 a wizard can be casting fly, but like only once per day, maybe twice and that's at the expense of having picked other spells. At 3-4 I would hardly call flight a "gimme".

[FMArthur]

What CR even meant was not entirely consistent in 3.5's monsters, but one good rule of thumb is that one creature of character level X is considered to have a CR equal to X. Thus, assuming balanced classes (pffthahahaha), one character should have a 50% chance of defeating a CR equal to his character level. Two such creatures are CR X+1. A full party-vs-party battle is actually CR X+2, although some might think that it is CR X.

Using this system, a party facing an equal-levelled CR isn't in too much danger, but that's apparently how an adventuring career is supposed to go and makes a certain amount of sense for retaining party stability; party members don't die frequently and challenge comes from stamina and resource management, since they should be expected to complete 4 such encounters per day. It also means slower XP/treasure progression than a more challenging adventure. Put together these things essentially mean that the gamier your group is, the more they will prefer greater challenges - which simultaneously awards them sped-up progression (in fact, +2 CR amounts to double XP), another thing that holds greater appeal to gamer groups.

I generally hover at around CR X+1 to X+2 and run only 2-3 encounters a day, since my group is gamier than most.



Battle conditions should modify CR if they don't occur due to massive party incompetence. The "Tucker's Kobolds" story is a good example of a DM thinking a party should overcome lower-level threats after giving their enemies every possible advantage, sowing disaster for the group, which is told often as a story about a 'clever' DM 'outsmarting' the players in a world he controls every aspect of.

My estimation of battle conditions' value is usually pretty vague, but here's what I've got:
Conditions massively impede players: +3 CR (party almost entirely unable to defend against or attack foes)
Battle conditions greatly impede players: +2 CR (party operating at ~50% effectiveness, meaning all are having difficulty affecting enemies or only half the characters can contribute)
Battle conditions minorly impede players: +1 CR (party operating at ~75% effectiveness, meaning all are somewhat reduced in their effectiveness vs enemies or 1/4 party members cannot contribute)
The party knows about the upcoming encounter and has more than a minute to prepare in advance: -1 CR.
The party knows about the upcoming encounter and has at least a day to prepare in advance: -2 CR.

...and then give the reverse adjustments (-3, -2, -1, +1, +2) to the encounter based on how restricted or prepared the enemies are on the same scale. For instance, fighting enemies at range in heavy rain might just work out to equality if the enemies are affected too, but if the party is blind in the Underdark fighting Drow, **** has officially hit the fan for your heroes. This is dependent on the party's abilities, so you have to know the party before using this. An ambush from clifftops is vastly different for melee-heavy parties (+2 or even +3 CR for them) compared to parties with ranged attacks and spellcasting, for example.

[RedWarrior0]

On a note related to CR confusion, where does it tell what an advanced monster is in terms of CR, or one with class levels? Do NPC class levels have different CR than PC classes (I'd assume so)?

[Eldariel]

On a note related to CR confusion, where does it tell what an advanced monster is in terms of CR, or one with class levels? Do NPC class levels have different CR than PC classes (I'd assume so)?

Improving Monsters (http://www.d20srd.org/indexes/improvingMonsters.htm)-chapter in the Monster Manual covers all that.

[RedWarrior0]

Improving Monsters (http://www.d20srd.org/indexes/improvingMonsters.htm)-chapter in the Monster Manual covers all that.
That makes me feel stupid. I was on that page when I asked that question and didn't see the right-hand column.

[Fax Celestis]

This approach works better, in my experience, if you give each of the orcs - or whatever substitute monster you're grouping - its own initiative. Done the other way, I've seen far too many encounters where the orcs swarm and destroy the party's tactics before they can deploy, or where the party spams damage on the orcs before they can do anything but show up and hand over the XPs.

People don't roll individual inits? :smallconfused:

[Diarmuid]

That also struck me a little strange. In anything but a very large battle with multiple "units" of monsters, our games always involve individual initiatives for all individual combatants (caveats made for familiars, animal companions, etc unless they take an intiaitive impacting action like delay/ready).

[Eldariel]

People don't roll individual inits? :smallconfused:

Having played lots of games with different GMs on Conventions, it appears to me people prefer the "one enemy type = one initiative" shortcut suggestion from the DMG. I mostly roll individual initiatives unless there's a lot of enemies, though (10+ enemies I generally run on group initiatives of at least 5 per group; doesn't hurt that these mostly occur in confrontations against a military force so it sorta makes sense too).

[Xtomjames]

Initiative in battle for monsters is really up to the DM. Each monster has their own initiative score, but in most cases (especially for new DMs) monsters tend to be exact copies of each other and thus rolling one initiative for the group makes it easier to keep track.

Again a simple rule for combat initiative is that if it is a horde of the same type (let's say goblins in this case) then just role the initiative for the goblins as a whole. If you, as a DM, don't want them to swarm then don't have them swarm.

If they're individual monsters (each with their own initiative) roll for each of them.

There is a reason why initiative works this way, most of the time a group of monsters will react at the same time to a threat, thus sharing the initiative. In some instances part of the monster's group may not notice the threat and thus react slower or not at all. It really depends on the style of the DM.

[Fax Celestis]

most of the time a group of monsters will react at the same time to a threat, thus sharing the initiative. In some instances part of the monster's group may not notice the threat and thus react slower or not at all.


most of the time a group of players will react at the same time to a threat, thus sharing the initiative. In some instances part of the player's group may not notice the threat and thus react slower or not at all.

Which is decidedly not the case. That's really neither here nor there, honestly, and probably deserves its own thread.

[Gnaeus]

Gnaeus, as with many posters here you're also assuming a certain level of optimizations. I would say that not many of the games I've been in has flight been "easy to come by" at levels 3-5. Sure, at level 5 a wizard can be casting fly, but like only once per day, maybe twice and that's at the expense of having picked other spells. At 3-4 I would hardly call flight a "gimme".

I wouldn't call a core-only druid with a core mount high op. The reserve feat is the rarest thing in it, which he could easily replace with a big bag of rocks and a sling. I mean, it does require looking at your list of animal companions, and thinking "hey, if I could fly, that would be handy", but not really a super high level of system mastery there.

The reason I listed it at level 3-5 is that it doesn't actually require flight in the sense of the spell. The tiger has no ranks in Climb, and it lives in forests. At level 3 the wizard can cast levitate. At level 3 most casters can summon a large centipede that can carry them into a tree, or at level 5 a hippogriff. If any tier 1, most tier 2s and some tier 3s can do something in core, I usually call it easily available. More options are available non-core. With a little warning, even muggles could likely make do with ranks in climb and some rope. (Climb is Str based, so the tiger will have a positive modifier, but at 12 feet long 6000 pounds it will logically have difficulty climbing to the same places as a 90 pound halfling.)

[Diarmuid]

I never said that flight was impossible. What I was arguing is that assuming every group is going to have it readily avalable from level 3-5 seems inappropriate.

In most of your examples, those strategies require time, skill checks, environmental variables, and multiple rounds to pull off. All the while you're assuming this tiger isnt charge/pouncing? And while the wizard might be able to levitate, he likely has fighter or rogue buddies who are going to get shredded.

I'm not looking to get into a battle of examples, I just thought your sweeping generalizations were misplaced.

[Gnaeus]

I never said that flight was impossible. What I was arguing is that assuming every group is going to have it readily avalable from level 3-5 seems inappropriate..

Fine. Because that wasn't what I was arguing. If every group had fly at level 5, why would I have bothered mentioning that it can TPK equal or higher ECL encounters in melee? Any group with core rules COULD have fly available by level 3-5, without resorting to high-optimization. A potion of levitate is only 300 gp. Heck, outside core, I think you can get it earlier with things like Raptorans or Kobolds.

My point was that the tiger, like some other monsters, is either going to be way underpowered (like, if you have access to flight), or way overpowered (like if it gets you into melee).

[Eldariel]

Fine. Because that wasn't what I was arguing. If every group had fly at level 5, why would I have bothered mentioning that it can TPK equal or higher ECL encounters in melee? Any group with core rules COULD have fly available by level 3-5, without resorting to high-optimization. A potion of levitate is only 300 gp. Heck, outside core, I think you can get it earlier with things like Raptorans or Kobolds.

Raptorans don't. Kobolds maybe kinda-sorta can. Either way, Alter Self is available on level 3 and that's all the fly you'll ever need.