Little confused about CMB vs. CMD.


Rules Questions


Quote:
CMB = Base attack bonus + Strength modifier + special size modifier

Okay, that much makes sense. But then...

Quote:
CMD = 10 + Base attack bonus + Strength modifier + Dexterity modifier + special size modifier + miscellaneous modifiers

So you're adding Strength AND Dexterity to CMD? Doesn't that make it unusually hard to perform a combat maneuver? Or am I missing something? Especially since some combat maneuvers require a standard action to perform, I'm tempted to drop the DC to 5 + whatever if you're adding TWO stats to it...


If you specialize for them they are not too hard, assuming you are going after medium sized creatures. Monsters start to get more difficult to deal with around level 10. They tend to be really strong, and more likely to have a size bonus. Monsters also tend to have good CMB bonuses so them working on players is much more likely at certain points also depending on the class.

When you do combat maneuvers with a weapon you also add the weapon bonus, and anything else that applies to that weapon.

Grand Lodge

Pathfinder Adventure, Rulebook Subscriber; Pathfinder Battles Case Subscriber
Raving Nerd wrote:
So you're adding Strength AND Dexterity to CMD? Doesn't that make it unusually hard to perform a combat maneuver? Or am I missing something?

The fact that most people don't have a high Str and Dex. And once you start getting up in level, the ability score bonuses pale in comparison to high BAB from massive HD, massive size bonuses, and other ridiculous bonuses to CMB. Go look at some high level grapplers and see how much adding your Dex into the equation matters.


Pathfinder Companion, Pawns Subscriber; Pathfinder Roleplaying Game Superscriber
Raving Nerd wrote:
Quote:
CMB = Base attack bonus + Strength modifier + special size modifier

Okay, that much makes sense. But then...

Quote:
CMD = 10 + Base attack bonus + Strength modifier + Dexterity modifier + special size modifier + miscellaneous modifiers
So you're adding Strength AND Dexterity to CMD? Doesn't that make it unusually hard to perform a combat maneuver? Or am I missing something? Especially since some combat maneuvers require a standard action to perform, I'm tempted to drop the DC to 5 + whatever if you're adding TWO stats to it...

You're missing the d20 roll you add to CMB.


TriOmegaZero wrote:
The fact that most people don't have a high Str and Dex. And once you start getting up in level, the ability score bonuses pale in comparison to high BAB from massive HD, massive size bonuses, and other ridiculous bonuses to CMB. Go look at some high level grapplers and see how much adding your Dex into the equation matters.

I'm not sure if that's good or bad. If the fighter wants to specialize in combat maneuvers, is he boned or will he be okay?


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Pathfinder Companion, Pawns Subscriber; Pathfinder Roleplaying Game Superscriber

In other words, a combat maneuver is CMB + d20 vs. CMD.

Grand Lodge

Pathfinder Adventure, Rulebook Subscriber; Pathfinder Battles Case Subscriber
Raving Nerd wrote:
I'm not sure if that's good or bad. If the fighter wants to specialize in combat maneuvers, is he boned or will he be okay?

Against humanoid opponents? Fairly effective.

Against everything else in the bestiaries? Most of them get straight immunity to maneuvers (can't disarm natural weapons, can't trip flying creatures, can't grapple incorporeal, etc) or effective immunity thanks to massive bonuses to CMD.


Pathfinder Companion, Pawns Subscriber; Pathfinder Roleplaying Game Superscriber
Raving Nerd wrote:
If the fighter wants to specialize in combat maneuvers, is he boned or will he be okay?

Dude, you ADD a d20 roll. It's no different than BAB + d20 vs. AC (except different numbers). Combat maneuvers are rather easy to pull off if you specialize in them.


taks wrote:
Raving Nerd wrote:
If the fighter wants to specialize in combat maneuvers, is he boned or will he be okay?
Dude, you ADD a d20 roll. It's no different than BAB + d20 vs. AC (except different numbers). Combat maneuvers are rather easy to pull off if you specialize in them.

And many spellcasters who get caught by surprise, or just find themselves in the wrong location adjacen to a grappler, become painfully aware of just how easy their CMD is to overcome.


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Pathfinder Companion, Pawns Subscriber; Pathfinder Roleplaying Game Superscriber

Indeed.

The biggest problem with combat maneuvers is the grapple flow chart. Ouch! :)


Raving Nerd wrote:
So you're adding Strength AND Dexterity to CMD? Doesn't that make it unusually hard to perform a combat maneuver? Or am I missing something? Especially since some combat maneuvers require a standard action to perform, I'm tempted to drop the DC to 5 + whatever if you're adding TWO stats to it...

Yes, CMD scaling is broken. I'd suggest going to the OGL 3.5 rules. They don't apply two stats to the same roll and except for the touch attacks required by some maneuvers all the rolls are "fair" (opposed str with or without size modifiers or opposed attack roll). I'd also remove the size bonuses/penalties except to bull rush since size already includes a strength modifier and all size effects apply to strength checks.

You need to come up with something for dirty trick and if they ever comes up drag and reposition. Steal in 3.5 is listed under disarm.

Dropping the DC to 5+ won't fix anything. It will just make it broken in two different directions depending on the opponent. Since enemies trend towards having much more than 5 excess CMD as CR increases that doesn't fix them being useless at high level and they will be ridiculously overpowered at low level and against PCs. The incorrect scaling and double dipping size bonuses have to be removed to actually fix the system.


Take a barb. lv5

CMB = 6 raging str + 5 bab = 11
CMD = 10 + CMB + 2 dex -2 rage AC penalty = 21

He needs to roll a 10 to hit himself. But we haven't factored in anything yet

CMB bonuses = magic weapons for some, feats, magic items.
CMD bonuses = deflection AC

So his CMB is at least +1 and likely +3 or +5
His CMD is maybe a +1

So new values
CMB = 14 or 16
CMD = 22

Now you only need an 8 or a 6 to succeed. Which isn't bad for this rough estimate start.

Fighter
CMB = 4 str + 5 bab + 1 weapon + 1 weapon focus + 1 weapon training + 2/4 focusing on maneuvers = 14/16
CMD = 10 + 4 str + 5 bab + 1 deflection + 2 dex=22

So a fighter needs a 10 against himself and an 8 or a 6 with a little specializing.

Cleric
CMB = str 4 + bab 3 + weapon 1= 8
CMD = 10 + str 3 + bab 3 + dex 2 + 1 deflection = 19

Your barb or fighter only need a 7 with no specialization and a 5 or 3 if you're focusing on maneuvers.

Wizard
CMB = str -1 bab 2 = 1
CMD = 10 + CMB + 2 dex +1 deflection = 14

barb/fighter needs a 2, specialized or not.

CMB works fine against humans, it just gets hard against monsters or immunity. Flight and trip, disarm and weaponless, etc.


Pathfinder Adventure, Adventure Path Subscriber
Raving Nerd wrote:
Doesn't that make it unusually hard to perform a combat maneuver?

Yes. But that's by design.

The intention behind combat maneuvers is not that they are successful as often as simply hitting and doing hit point damage. Doing damage, you often will need to hit five, six, or more times in order to incapacitate someone. Doing maneuvers, you've got things like disarm, and often grapple, which can finish a fight very quickly.

CMD also gets dodge, luck, and deflection bonuses stacked on it, FYI.

CMB gets your weapon enhancement bonus if you're using a weapon to perform the given maneuver.

Basically, maneuvers aren't intended to work often.


Chess Pwn wrote:

Fighter

CMB = 4 str + 5 bab + 1 weapon + 1 weapon focus + 1 weapon training + 2/4 focusing on maneuvers = 14/16
CMD = 10 + 4 str + 5 bab + 1 deflection + 2 dex=22

So a fighter needs a 10 against himself and an 8 or a 6 with a little specializing.

Only because you've built a straw fighter with only 10 dex. NPCs aren't built like that. They'll be built from a 15/14/12/11/10/8 array. That will leave any martial with 14 or 12 dex. Only the barbarian is vulnerable to maneuvers relative to his BAB.

Monsters are much worse. Except moving from diminutive to fine increasing a monster's size always raises strength by at least as much as it reduces dex and this on top of the direct size bonuses. Past small the increase to strength is always larger than the decrease in dex.
http://www.d20pfsrd.com/bestiary/rules-for-monsters/monster-creation


Atarlost wrote:
Chess Pwn wrote:

Fighter

CMB = 4 str + 5 bab + 1 weapon + 1 weapon focus + 1 weapon training + 2/4 focusing on maneuvers = 14/16
CMD = 10 + 4 str + 5 bab + 1 deflection + 2 dex=22

So a fighter needs a 10 against himself and an 8 or a 6 with a little specializing.

Only because you've built a straw fighter with only 10 dex. NPCs aren't built like that. They'll be built from a 15/14/12/11/10/8 array. That will leave any martial with 14 or 12 dex. Only the barbarian is vulnerable to maneuvers relative to his BAB.

Monsters are much worse. Except moving from diminutive to fine increasing a monster's size always raises strength by at least as much as it reduces dex and this on top of the direct size bonuses. Past small the increase to strength is always larger than the decrease in dex.
http://www.d20pfsrd.com/bestiary/rules-for-monsters/monster-creation

The fighter has a dex of 14. Hence the + 2 dex part of the CMD equation. It's a figher with str 18 and dex of 14. I feel it's a decent example, extreme cases might be one or two points higher, but for the majority my example is right on.

But yes, monsters get hard a lot faster than classes do.


Another question: does the difficulty of CMD checks weaken the ability to move in combat, or is it possible to raise Acrobatics enough to offset this?


You can raise acrobatics enough to have an okay chance of aboiding AoOs, but there will be risk with some opponents. I personally like it that way.


Raving Nerd, I am not sure what your are talking about difficulty of CMD checks and moving in combat? CMD is not effected at all by moving in combat, unless you are entangled or fatigued ect. but it not the moving cause it, it is the other conditions are you talking about choose to fight defensively or go full defensive, and use the dodge bonus granted by that, which is higher if you have 3 ranks acrobatics to raise your cmd. If so yes that can be done. Also combat expertise also applies. Remember all dodge bonus stack so long as they are not from the same source, but they can also be lost by being caught flat-footed or things that normally deny you your dex bonus.

CMD is very easy to raise. deflection, insite, favored class bonus, race bonus, the list goes on and on. there are more ways to raise your CMD then there is to raise your CMB hence even a specialists at the upper levels can have problems against CMD. Mid levels it tend to work very well against humanoid creatures.


against humans, pretty easy.

10 ~ roll
bab = skill ranks
str and dex ~= dex + fcb
misc bonuses ~ misc bonuses

so going against non-full bab is nicer, or low physical scores. But monster's CMD can scale quite fast.

The main thing to find out is, are you fighting mostly humanoids or monsters? That is a large part of if maneuvers are worth looking at.
Fighting oozes, dragons, devils and demons, probably not. Fighting the army of the the neighboring nation, worth looking at.

Scarab Sages

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Raving Nerd wrote:
TriOmegaZero wrote:
The fact that most people don't have a high Str and Dex. And once you start getting up in level, the ability score bonuses pale in comparison to high BAB from massive HD, massive size bonuses, and other ridiculous bonuses to CMB. Go look at some high level grapplers and see how much adding your Dex into the equation matters.
I'm not sure if that's good or bad. If the fighter wants to specialize in combat maneuvers, is he boned or will he be okay?

Specialists will always have areas they are boned and areas they excel.

For the Fighter class, having at least one maneuver that you are good at will proved very helpful.

Sunder is a common choice, but has the disadvantage of not working against natural weapons and the major disadvantage of potentially destroying valuable loot.

Disarm is a very viable fighter choice. It both offers a way to non-lethally defeat humanoid opponents, and the fighter is very weapon dependent, so the Disarm feats adding to CMD against such maneuvers is very valued to the fighter. Disadvantage is that not all opponents wield weapons that can be disarmed.

Trip is another good choice, but many things are immune to trip, plus there are builds where they focus on fighting while prone. Like disarm, trip feats increase your CMD to trip, which can be very useful for fighters, as they can be rather impaired by this maneuver.

Bull, Drag and Reposition are all variants of moving the opponent around the field. They can be useful, but are largely dependent on terrain or allies to create situations where moving the opponent is advantageous.

Steal is less useful for most fighters because it requires a free hand. It otherwise can be very impressive, especially if used on unwielded wands, scrolls, potions, and holy symbols.

Overrun is a neat one, as it allows you to move past opponents. Speed is rather important on this one, so it's more common for mounted characters.

Grapple is very useful, but also requires free hands and the improved unarmed strike feat, making it somewhat iffy for fighters. The increases to CMD against grapple are very useful, as it is a very common monster ability (grab attacks).

Dirty Trick is probably the most versatile combat maneuver, but also the one most subject to table variance.

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