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Frosty
2008-09-17, 02:27 PM
I was looking through monsters from different monster manuals and different books, and I'm having a hard time figuring out a way to assign CRs. there just doesn't seem to be any consistency. For example, how is that Giant Crab comparable to other CR3s or a Fleshraker to other CR2s? Looking on the other end of the scale, a Balor is CR20 yet Malconthet, the Queen of the Succubi with 415 HP, save DCs in the high 30s, scary-ass (Su) and (Sp) abilities and has similar combat damage is only a CR21?

How exactly is CR determined anyways? Is there some sort of formula for it or did WotC just eyeball things...while very drunk? I will be tyring to design some new devils on my own, and I'll need help with assigning their CR.

kamikasei
2008-09-17, 02:31 PM
Arbitrarily and badly. But there are suggested guidelines on the homebrew forum.


I've seen a variety of methods to set CRs on creatures, but I've really only found two that work 95% of the time. The first is the one I use: the creatures CR should be between a 3:2 to a 1:1 ratio for BAB:CR, generally, so that a BAB of +9 would be a CR between 6 and 9.


A challenge rating is how tough an encounter with this beast will be. Generally a creature of, say, a CR of 5 should be a standard challenge for a party of 4-5 5th level characters. To defeat this creature will cause them to use up roughly 1/4th to 1/3 their daily resources such as spells, potions, etc. This depends on the build of the party, their items, terrain, and many other factors, but in general it is more or less accurate.

Figuring out this challenge rating is the real fun part, and probably the most challenging bit of monster making. Its as much guestimating as anything, and there are no true rules to determine it exactly. Here is the closest method I've been able to come up with, though creatures with an enormous ammount of hit points or really low-leveled creatures will still be innacurate. The best way is to play-test the creature with parties of varying CR and find out which one most closely fits. Here though is the guestimator method:

#1. Divide creature's average HP by 4.5 to 6.5.
4.5 for 5 HD or lower, 5 for 6-10 HD, 5.5 for 11-15 HD, 6 for 16-20 HD., 6.5 for 20-25 HD.

#2. Add 1 for each five points above 10 its AC is, subtracting 1 for every 5 below.

#3. Add 1 for each special attack (+2 to +5 or more if its got a decent number of spells in its spell-like abilities).

#4. Add 1 for each quality unless you deem it worthy of more. Add 1 for each resistance and 10 points of DR it has, and 2 for each immunity. Subtract 1 for each vulnerability.

#5. Add 1 for every two bonus feats it has.

#6. Divide total by 3. This should be its rough CR.

Duke of URL
2008-09-17, 02:31 PM
I usually just guess, but then again, creature design is not one my strengths.

mostlyharmful
2008-09-17, 02:32 PM
did WotC just eyeball things...while very drunk?

Do you really have to ask?

Sarcasm aside CR depends on the capabilities of your PCs, to be honest eyeballing it with specific details of the campaign and Characters in mind is about the only way that makes sense.

Starsinger
2008-09-17, 02:35 PM
The standard method is to guess until you get it right, kinda like spellschools, IMO.

Frosty
2008-09-17, 02:45 PM
I don't want to have to test it out on my party. Because then they might die from it. I mean, it just seems wrong than a level 22 Warrior has the same CR as Malconthet. They are CLEARLY not the same strength. I'm not sure any non-full-caster character at level 20 can really challenge the likes of her, while there are PLENTY of builds that can just pwn the level 22 Warrior.

afroakuma
2008-09-17, 03:15 PM
Take some of the DMG's generic NPCs and run a simulated combat. Often works for me.

But yeah, CRs, even *cough*especially*cough* WotC's own, are often a major crapshoot. MMII's Hellfire Wyrm, a spellslinging hell dragon, has the same CR (26!!!) as MMII's Mountain Giant, a really big giant who can... is really big.

One suggestion I read somewhere: Create monster, assign CR where you want it to be, then adjust the monster until it matches your desired CR.

Frosty
2008-09-17, 03:17 PM
Take some of the DMG's generic NPCs and run a simulated combat. Often works for me.

But yeah, CRs, even *cough*especially*cough* WotC's own, are often a major crapshoot. MMII's Hellfire Wyrm, a spellslinging hell dragon, has the same CR (26!!!) as MMII's Mountain Giant, a really big giant who can... is really big.

One suggestion I read somewhere: Create monster, assign CR where you want it to be, then adjust the monster until it matches your desired CR.

But how do I know if the monster needs adjusting to say...fit the CR15 I want? DMG generic NPCs are in no way shape or form representative of the PCs, imo. They kind of...suck.

insecure
2008-09-17, 03:19 PM
I don't want to have to test it out on my party. Because then they might die from it. I mean, it just seems wrong than a level 22 Warrior has the same CR as Malconthet. They are CLEARLY not the same strength. I'm not sure any non-full-caster character at level 20 can really challenge the likes of her, while there are PLENTY of builds that can just pwn the level 22 Warrior.

Keep in mind that NPC classes only have half the CR compared to a PC class at the same level.

Frosty
2008-09-17, 03:19 PM
Keep in mind that NPC classes only have half the CR compared to a PC class at the same level.

I remember reading that NPC classes have PC class minus 1 for CR?

Prometheus
2008-09-17, 03:20 PM
The easiest means is to take an existing creature and mod the crap out of it.

The official means of determining CR is to test against a standard party (equivalent to what is in the DMG for PC NPCs rather than your more typical optimized), (roles: melee, skillmonkey, healing, and magic). Of course, this is the same system they used to generate the Monster Manuals and set up class balance.

Vorpal Tribble's (already posted) works pretty well.

Frosty
2008-09-17, 03:22 PM
Perhaps when WoTC tested their monsters they had evocation specialist Wizards, healbot clerics, Sword and Board Fighters, and non-multiclass rogues?

Starbuck_II
2008-09-17, 03:29 PM
I was looking through monsters from different monster manuals and different books, and I'm having a hard time figuring out a way to assign CRs. there just doesn't seem to be any consistency. For example, how is that Giant Crab comparable to other CR3s or a Fleshraker to other CR2s? Looking on the other end of the scale, a Balor is CR20 yet Malconthet, the Queen of the Succubi with 415 HP, save DCs in the high 30s, scary-ass (Su) and (Sp) abilities and has similar combat damage is only a CR21?

How exactly is CR determined anyways? Is there some sort of formula for it or did WotC just eyeball things...while very drunk? I will be tyring to design some new devils on my own, and I'll need help with assigning their CR.
The Giant Crab is known to be low balled in CR. It should be higher.

Chronos
2008-09-17, 03:29 PM
The best method, if you've got the time, is to construct a "standard" party of four characters, and run a few test fights between the party and the monster for each level of the party. When the party of level X beats the monster without too much difficulty, but the party of level X-4 gets wiped out about half the time, you've got it.


Perhaps when WoTC tested their monsters they had evocation specialist Wizards, healbot clerics, Sword and Board Fighters, and non-multiclass rogues?That seems to be the concensus. So if you're trying to match the CRs of published monsters (such as they are), that's more or less the party you should be using. Then remember that your players are probably using something better, and shift everything that they're fighting (published and homebrew) by a few CRs.

mostlyharmful
2008-09-17, 03:51 PM
I remember reading that NPC classes have PC class minus 1 for CR?

Oh? so the level 22 Warrior is CR 21? And this is significantly better?

Frosty
2008-09-17, 03:55 PM
Oh? so the level 22 Warrior is CR 21? And this is significantly better?

I didn't say I agreed with the formula, but I remember the DMG saying it. Frankly, I'm not sure about the whole: a Level X PC is a CR X challenge.

It implies that two CR X creatuers are about as tough as each other, and I'm pretty sure that most level 21 characters are NOT the equivalent of Malconthet, and most level 20 characters are't the equivalent of a Balor.

FMArthur
2008-09-17, 04:04 PM
The Giant Crab is known to be low balled in CR. It should be higher.

I can't even remember the last time I saw THAT DAMNED CRAB referred to by its official name, Giant Crab. Took me a while to find it when I first heard of it because I didn't know its real name, just That Damned Crab. Apparently a source of many horror stories of early-campaign unplanned TPKs.

Frosty
2008-09-17, 04:08 PM
I can't even remember the last time I saw THAT DAMNED CRAB referred to by its official name, Giant Crab. Took me a while to find it when I first heard of it because I didn't know its real name, just That Damned Crab. Apparently a source of many horror stories of early-campaign unplanned TPKs.

I wonder where that nickname came from.

Sstoopidtallkid
2008-09-17, 04:12 PM
I wonder where that nickname came from.Yeah, it doesn't seem applicable at all.

@the OP:Here's WotC's method, as I understand it:Get a mini of every monster you want to assign a CR to. Superglue a spike to the top of each mini. Get a dartboard. Get a blindfold. Get really, really drunk. Throw. The resulting score is the CR of the mini.

kjones
2008-09-17, 04:13 PM
For creating monsters with a CR of 1-20:

1. Follow closely the guidelines set down for advancement in the SRD.
2. Cross-check with Vorpal Tribble's rules of thumb - adjust as necessary. I recommend a geometric mean (http://en.wikipedia.org/wiki/Geometric_mean)as a method that maintains proper mathematical weight between the two.
3. Playtest repeatedly with a set of generic PCs. If necessary, playtest with your actual party. You'll want to do this at least ten times, for optimum statistical merit.
4. Throw away all the data you've just collected.
5. Roll 1d20. The result is the creature's CR.

EDIT: I... can't believe this suggestion was essentially just ninja'ed.

Eldariel
2008-09-17, 04:23 PM
That Damn Crab has the annoying feature that it's immune to all ways of solving physically tough encounters on that level. Amusingly enough, for example a Purple Worm is not. So I'd be more frightened by That Damn Crab than Purple Worm on level 3 (and yes, I've been in a party that killed a Purple Worm on level 3 [Touch of Idiocy] - incidentially, the last party that faced The Crab experienced a Near TPK with the Wizard Alter Selfing into Avariel and getting the heck out of there; last time I pit a Crab vs. level 3 party...).

Frosty
2008-09-17, 04:26 PM
Maybe pit the crab against a level 6 party? The raging barbarian with 26 strength and Improved Grapple has an ok chance I guess...

Eldariel
2008-09-17, 04:30 PM
Eh, the way to beat it is still to stay the hell out of the grapple. But a level 5 party could have a decent chance; with some form of transportation spells, Level 3 Stance (Roots of the Mountain), just plain higher AC and AB, access to flight and so on, a level 5 party is well equipped to defeat it (obviously it'll submerge if you take flight, but that's enough to "win" the encounter). Level 6 means you can have Shock Troopers and they can probably one-shot it as it has a low AC. So it isn't that scary, it's just scary for a level 3 party since it's physically tougher than any normal level 3 characters and immune to most Magic.

Starbuck_II
2008-09-17, 04:34 PM
Maybe pit the crab against a level 6 party? The raging barbarian with 26 strength and Improved Grapple has an ok chance I guess...

I think that the Crab is kinda CR 5ish. I mean, that would be when most parties can beat the thing only using 20% resources.

Frosty
2008-09-17, 04:38 PM
Eh, the way to beat it is still to stay the hell out of the grapple. But a level 5 party could have a decent chance; with some form of transportation spells, Level 3 Stance (Roots of the Mountain), just plain higher AC and AB, access to flight and so on, a level 5 party is well equipped to defeat it (obviously it'll submerge if you take flight, but that's enough to "win" the encounter). Level 6 means you can have Shock Troopers and they can probably one-shot it as it has a low AC. So it isn't that scary, it's just scary for a level 3 party since it's physically tougher than any normal level 3 characters and immune to most Magic.

Shock Trooper? You're going to lower your AC when your charge will provoke an AoO, allowing it to hit you adn then use it Improved Grab to stop your charge?

Sstoopidtallkid
2008-09-17, 04:42 PM
A good chunk of the problem with the CR system is that there's so many invisible lines where something goes from 'no challenge' to 'TPK'. The Crab, for instance, can TPK any 4th level or lower party. A 5th level party can win, but will have trouble, and may lose a member. By 6th level, it shouldn't take many resources at all to beat TDC. There is no CR that's appropriate for that.

Frosty
2008-09-17, 04:48 PM
But where is that line and how can I avoid it when designing monsters? I want to design cool, memorable, and challenging encounters without it turning into a TPK.

Back to the Giant Crab, a party is supposed to wipe 50% of the time against a creature of their average party level + 4 correct? If the crab wipes a level 3 party almost 100% of the time, then doesn't that mean it's above CR 7?

Eldariel
2008-09-17, 04:56 PM
Shock Trooper? You're going to lower your AC when your charge will provoke an AoO, allowing it to hit you adn then use it Improved Grab to stop your charge?

It's Large. You have a Reach Weapon. You're not provoking.

Sstoopidtallkid
2008-09-17, 04:59 PM
But where is that line and how can I avoid it when designing monsters? I want to design cool, memorable, and challenging encounters without it turning into a TPK.

Back to the Giant Crab, a party is supposed to wipe 50% of the time against a creature of their average party level + 4 correct? If the crab wipes a level 3 party almost 100% of the time, then doesn't that mean it's above CR 7?Except a level 6 party can kill it easily, and a solo Warrior at level 10 can crush it. That's the problem, some creatures just aren't able to be statted well.

Heck, if you really want a TPK, Venerable Dragonwrought Kobold Adept 4. CR1. Make the party beg for mercy.

Starbuck_II
2008-09-17, 05:02 PM
But where is that line and how can I avoid it when designing monsters? I want to design cool, memorable, and challenging encounters without it turning into a TPK.

Back to the Giant Crab, a party is supposed to wipe 50% of the time against a creature of their average party level + 4 correct? If the crab wipes a level 3 party almost 100% of the time, then doesn't that mean it's above CR 7?

Glitterdust, Grease, and running work. It only has a 40 speed on land! Dude, it is as fast as a Barbarian in light armor (or naked monk).

Glitterdust because it has low Will saves and Glitterdust isn't affected by vermin traits.
But that won't last long and it stills have 66 hps!

Still a Level 5 party shouldn't lose.

Frosty
2008-09-17, 05:04 PM
You have a Reach Weapon.

Not always true.

Eldariel
2008-09-17, 05:18 PM
Not always true.

I have yet to meet a melee character who doesn't at least carry a reach weapon around (Guisarme costs you what, 9gp? You're level 6 with 13000gp) for when you might need it. Facing a Giant Crab is a case of "needing it". Also, if you're a charger, you'll really want that reach since having to go through opponent's threatened square provokes an AoO and 2 extra damage from Greatsword (especially with the numbers Chargers pull off) just isn't worth taking an almost certain hit to the face, especially since that hit may also be a trip, a grab or any other number of very unpleasant things (that, most importantly, can prevent you from delivering the charge).

Chronos
2008-09-17, 05:19 PM
Glitterdust, Grease, and running work. It only has a 40 speed on land! Dude, it is as fast as a Barbarian in light armor (or naked monk).This sounds a lot like the old joke about the hiker wearing running shoes in bear country. Unless your party is made up entirely of barbarians and monks, someone's going to get eaten. Really, the one virtue of the Crab is that it won't ever TPK, since it goes home to eat after it's caught two targets.


A good chunk of the problem with the CR system is that there's so many invisible lines where something goes from 'no challenge' to 'TPK'.Sometimes, the answer to this is to just decide how you're going to use the monster, and stick to it. Orcs, for instance, are about at the right CR, in the sense that four orcs are a good encounter for a level 3 party, or eight orcs for a level 5, but two orcs for a level 1 party are likely to kill someone (even though those are all theoretically CR equal to the party level). So the solution is to just make sure that you use multiple orcs at higher levels, not a few at low levels.

Frosty
2008-09-17, 05:32 PM
Wait, that damned crab can grapple more than 1 opponent at a time?

Sstoopidtallkid
2008-09-17, 05:49 PM
Wait, that damned crab can grapple more than 1 opponent at a time?2 Claws, 2 grapples. Here (http://wizards.com/default.asp?x=dnd/fw/20040221a). Look upon it and wonder.

Frosty
2008-09-17, 05:52 PM
Well, I know what NOT to do when designing a creature.

Does anyone have tips on designing a balanced and fun creature?

Sstoopidtallkid
2008-09-17, 06:00 PM
It's worse than how it looks, even. Read it's tactics. It charges out of the water, striking whichever party member looks weakest in a surprise round. A Half-Orc with full BAB has a +9 grapple, +13 if it's a Grappler, and probably about 17 AC, depending on stats and where he spent WBL. So whichever party member was grappled loses. It probably loses Initiative, so the party gets one round of attacks, and the meat party member gets a chance to break(yeah, right). TDC then hits a second member, wins the grapple, and retreats back below the waves.

Not a TPK, but almost more insulting.

arguskos
2008-09-17, 06:09 PM
Does anyone have tips on designing a balanced and fun creature?
Well, I know how I do it, which may or may not be helpful to you.

Step 0: Pick a type.
This is easy. Pick your monster type. Odds are, you already have this.

Step 1: Pick a tactic.
This is the key thing I do when I make monsters (rarely, to be sure). I pick how the damn thing acts. Once I know what it's general plan is, then I can go from there. For example, if I was making a new elemental, I might decide to go with a spell-like ability blaster elemental who stands back and throws spells at the party from behind some lesser minions.

Step 2: Pick special abilites.
Once I have the critter's tactics in hand, I make up a special ability or two for him to use. In the example above, I decided to make a spell-slinging elemental blaster. He might benefit from some solid spell-like abilities (fireball, scorching ray, haste, whatever). Maybe I'll give him a basic "I shoot it with fire" attack, or maybe a flame wave attack that is like a bull rush + light damage, so he can set the tempo of the fight. Stuff like that.

Step 3: Stat him out.
Do the number-crunching part. You know, HD and all that jazz.

Step 3.5: If he has minions, pick them.

Step 4: Playtest him in his encounter of choice a few times.
Tweak as needed. Have too many abilites? Tone them back a little.

-argus

Frosty
2008-09-17, 06:09 PM
But how does it maintain its grapple? When you use one limb to grapple someone so you can do something else as if you weren't in a grapple, you take a -20 to your grapple checks don't you?

bosssmiley
2008-09-18, 03:29 AM
Get drunk. Throw darts at a standard dartboard. It obviously worked for WOTC. :smallwink:

Charity
2008-09-18, 04:10 AM
Get drunk. Throw darts at a standard dartboard. It obviously worked for WOTC. :smallwink:

you forgot to shut your eyes and spin round till you're dizzy.

Sstoopidtallkid
2008-09-18, 04:38 AM
Has anyone ever made up a calculator? I'm thinking one similar to the Weapon Balance Table (http://forums.gleemax.com/showthread.php?t=694416). The system posted earlier leaves too much up to adjudication, IMHO.

Charity
2008-09-18, 05:07 AM
VT's is the only half-hard system I know of, I'd use that, he is the Dr Frankenstien of the boards.

bosssmiley
2008-09-18, 07:20 AM
VT's is the only half-hard system I know of, I'd use that, he is the Dr Frankenstien of the boards.

"That's Frunk-en-steen!" :smallbiggrin:

Charity
2008-09-18, 08:28 AM
Vt at home
http://www-bdnew.fnal.gov/hq/mcginnis/rfcourse/RF_Meas_Class/young-frankenstein.jpg

Frosty
2008-09-18, 10:45 AM
I don't think I've seen a lot of Vorpal Tribble's posts myself. What else ahs he done?

Charity
2008-09-18, 11:01 AM
Start here (http://www.giantitp.com/forums/showthread.php?t=43009)

Frosty
2008-09-18, 11:09 AM
That's a very nice guide for beginners on the basics to monster creation by defining what's what. Not exactly what I'm looking for, but neat none-the-less. Is it stickied?

bosssmiley
2008-09-19, 04:01 AM
I don't think I've seen a lot of Vorpal Tribble's posts myself. What else ahs he done?

Follow the link in my sig.

VT could fill a Monster Manual with the creatures he's created. They won't let him do that though, because it would make WOTC's monster-makers cry at their own inadequacy and raise the bar insanely high for anyone who followed.
It'd be Hendrix at the Clapton concert all over again. :smallamused:

Reinboom
2008-09-19, 04:23 AM
I wonder where that nickname came from.

It was referred to first on these boards as this by Fax Celestis.
Fax Celestis ran the encounter using the advanced giant crab against his party for... I believe it was White Plume Mountain (or, adventure by similar name)... about 10 months ago it seems like.
The party being ECL 8, including a goliath charger (unsure of class, Jack_Mann's char IIRC), a rogue with the.. dark template I think (Shiny, bearer of the pokystick's character), a Favored Soul of Kord (Mike_Lemmer's character), a Ursine Barbarian (or, I think it was a Barbarian... Roland St. Jude's char) and a utility/buff Sorcerer (my character).

There was also a level 14 Ranger with that damned crab. The level 14 ranger went down in a little over a single round and didn't really do anything. That damned crab lasted many a round of struggling however, and many of us would have been gone if it hadn't been for Fax forgetting a rule.


For CR, I normally adjust my monsters on the spot with minor tweaks in order to try to balance them out and just ignore the CR system altogether (offering XP in manners of difficulty and brilliancy based on how the party got through that situation). Or, more likely, most encounters are more objective based with the dangerous parts (the enemies themselves) even less loosely tied to it, or in a broad enough situation that in the cases of me overpowering the party the party should be able to pull tricks from their surroundings.

It tends to make the game more interesting for both me and the players. Screw CR.

-edit-

Oh, one thing I do do to try to form a balance is I have a massive banned list (targeting more specifically to certain... resourceful NPCs of mine), and I try to set situations up in manners that allows the PCs, at their core, affect the encounter.

Frosty
2008-09-19, 11:12 AM
Wait, ECL 8 party almost died to that Crab? :smalleek:

RebelRogue
2008-09-19, 11:28 AM
Frankly, I'm not sure about the whole: a Level X PC is a CR X challenge.
Well, if anything that's the basis for how the CR system should (and I stress should) work.

Frosty
2008-09-19, 11:36 AM
I'm more interested on how it *does* work than how it should, so I can make the tweaks I need.

RebelRogue
2008-09-19, 12:01 PM
I'm more interested on how it *does* work than how it should, so I can make the tweaks I need.
It is the way to gauge it. It's the definition of CR made to make the game balanced/interesting according to ECL. That WotC sometimes has made some over/undershooting shouldn't skew the basic idea, unless you make up a new standard yourself and rework all the CRs.

Recaiden
2008-09-19, 12:18 PM
Wait, ECL 8 party almost died to that Crab? :smalleek:

I believe they gave the crab a few extra hit dice. After all, it was only CR 3. What's the worst that could happen?
That is my main problem with the CR system in 3.5: Such a fine line between cakewalk and TPK.

Frosty
2008-09-19, 12:26 PM
A few extra hit-dice *should* not a TPK make. Jeez...

Chronos
2008-09-19, 12:35 PM
VT could fill a Monster Manual with the creatures he's created. They won't let him do that though, because it would make WOTC's monster-makers cry at their own inadequacy and raise the bar insanely high for anyone who followed.
It'd be Hendrix at the Clapton concert all over again.There's also the slight matter that several of the Tribbles critters are, by themselves, quite adequate to induce insanity. I'm not talking about "roll a will save with DC set by the monster's Cha and HD", I mean inducing insanity in the players.

Frosty
2008-09-19, 12:38 PM
Oooh...give me an example here?

sonofzeal
2008-09-19, 01:44 PM
I, too, am curious for an example. :smallcool:

bosssmiley
2008-09-19, 03:30 PM
The Momeh (http://forums.gleemax.com/wotc_archive/index.php/t-652875). Just read the description. The thing is pure nightmare fuel. The more you think about it the more horrible it becomes. :smalleek:

Frosty
2008-09-19, 09:56 PM
Nice. I don't like using swarms, but very nice! Is there like a compendium of all his creations?

Collin152
2008-09-19, 11:09 PM
Also, I have no link, but the Eunichorn... or however it was spelled...
Vindictive little runt of a two-bit surgeon...

Chronos
2008-09-19, 11:45 PM
Also, I have no link, but the Eunichorn... or however it was spelled...
Vindictive little runt of a two-bit surgeon... Yeah, the eunuchorn (http://www.giantitp.com/forums/showthread.php?t=83875) is one of the ones I was thinking of... I seem to recall something about an undead baby swarm, too, but I can't seem to find it.