Monster Classes: Reworking Types/Subtypes, HD, etc from the Ground Up

[noob]

I think an even bigger problem is the inextricable linking between monster HD, monster skillpoints, and monster BAB

It is because fundamentally monsters are just adventurers but with some odd traits.
it is the same link as the link between adventurer hd, adventurer skill points and adventurer bab.

[Durzan]

It is because fundamentally monsters are just adventurers but with some odd traits.
it is the same link as the link between adventurer hd, adventurer skill points and adventurer bab.

Exactly. The problem is that those things are determined by type, not the monster's niche, which can vary from monster to monster regardless of what monster type they generally are. Hence why monster HD needs to be separated from Type.

[PairO'Dice Lost]

Not any HD range, but lower than would be appropriate for most monsters. Like we've been mentioning, the basilisk and other death gaze creatures are generally considered puzzle monsters. A basilisk is appropriate for its CR because it has -1 Init, a single unimpressive melee attack, a 20' move speed, and tactics that include giving "a half-hearted pursuit" to any PCs that run away / regroup when their strategy fails. In contrast, a Medusa is +2 CR because it has a shortbow, 30' move speed, and supposedly a high enough Bluff check to get it into gazing range. This sort of design should be done regularly. If your monster-generation method doesn't allow designers to trade abusable weaknesses for early access to scary monster powers, I would argue it fails to capture an important element of monster design.

Ah, I think we were talking past each other there. I was actually talking HD minima, not CR, and was implicitly accounting for the "being slow and stupid gives -X CR" part, because I don't think it's possible to rate individual abilities by CR in a vacuum rather than looking at the whole monster.

So yes, you can totally have a 6 HD creature with a petrifying gaze that could vary from CR 4 to CR 8 based on its other abilities, but you wouldn't have a specific "Is A Dumb Meatbag: This monster can't take [list of things], reduce CR by -2" ability, you'd just give it the gaze, the move speed, etc. and judge that the resulting package is CR 4. If that's what you were thinking of anyway, then we're on the same page.

The key thing for me is that the petrifying gaze shouldn't be available at 4 HD just because it's available at CR 4, because then you can make dumb 4-HD meatbags at CR 2 and so forth, and at some point you do reach a floor where a certain ability is inappropriate for monsters of a given CR. Granted, the boundaries are fuzzier at low levels since you can die or be removed from play for pretty much everything, but the principle gets to be more important at mid levels when a difference of a few points of CR or HD can mean the difference between "The party cleric has the removal spell for this condition, he can rest and have you fixed up tomorrow morning" and "We gotta go back to Waterdeep and spend a bunch of time and gold to get this taken care of."

To the table: if there are only class features every other level, then you create a weird system where puzzle monsters at CR 1 & 2 / 3 & 4 / 5 & 6 are close in power level, whereas 2 & 3 / 4 & 5 / etc see enormous power jumps. If level 4's feature is bonus HD and a stat boost, while level 5's feature is "death gaze", your designers and players are going to have a bad time. If we need to craft our design tool so that it creates wonky outputs for 50% of all CRs, then I think our design tool isn't useful.

I didn't mean to imply that monster classes would literally be one feature every other level, just that those specific abilities would progress at those levels. I didn't write in any sort of "And at this level it gets something related to natural armor or energy resistance" since it wasn't germane to the example and might have led to bikeshedding.

While we're on the topic, though, the general pattern I had in mind was to divide things up into different lists by specificity (generic monster abilities vs. abilities by monster class) and ability type (active offensive, active defensive, active offensive, and so on) and have different classes progress those at different rates. So Meatbag might have a few selections for generic passive offensive abilities like Knockback or Improved Grab, a bunch of generic passive defensive or generic stat increase abilities like DR or Con boosts, and one or maybe two Meatbag-specific passive offensive or defensive abilities like a flanking-related ability or some kind of Death Throes; Mastermind select the majority of its abilities from a Mastermind-specific "choose a level-appropriate mind-control/summon/animation/etc. SLA" list and a handful from a generic stat increase list for Int and Cha bonuses; and so forth.

A monster class, like all classes, is part of the social contract at the table. That social contract has long established that class features are balanced and interchangeable when offered at equal levels. That is true (or supposedly true) for all classes with select-able class features... except monster classes now. This is unlike the warmage, because the features of the warmage are all available to you from the moment you crack open Complete Arcane.

While we've been calling these things "monster classes" as shorthand to imply systematization and distinguish them from "types" and "roles" as used in 3e and 4e, they're really more of a build-your-own-monster-classes system. The comparison shouldn't be to a wizard, where you hand a player the class and say "go nuts" and the output is a particular build (which you fervently hope fits in with the rest of the party power-wise, because the "class features at a given level are balanced and interchangeable" thing is a blatant, blatant lie), but rather to the 2e DMG's custom class-building system where you hand the DM the system and the output is a particular class for a player to take.

And just like with that class-building system, while you certainly can hand it to a player to create a class as desired, the class produced is strictly subject to DM veto or alteration and doesn't have the automatic approval that choosing to play a Warmage after the DM has allowed all classes in Complete Arcane does.

Attempting to thread the needle here gives you a kind of pseudo-class. Players can't just use it to build their character, the only people who get free reign over it are DMs / designers, and the class needs cautionary warnings so that you don't combine 2 synergistic features to build an overpowered monster. That doesn't sound like a monster class to me. It sounds like a set of design guidelines. I'd much rather lean into these being guidelines and do away with the rigidity of pseudo-class-features.

The problem with that is that, quite frankly, most DMs are bad at designing custom opposition even within the normal system constraints, much less homebrewing something. Most DMs' first homebrew class or monster is terrible and unbalanced, most DMs' first BBEG is built like a player instead of like a good boss and either wrecks the party or dies like a chump, and most DMs are scared of letting random other peoples' homebrew into their games--even when that homebrew is by "known good" 'brewers and endorsed by people they know--because they're not confident in their ability to judge its balance.

No amount of guidelines that end up saying "...and then fiat something here, we're sure you've got this!" are going to turn out as well as hard mechanics that a new, uncertain, or just bad-at-design DM can follow explicitly, if only due to the fact that a single DM's design chops pale in comparison to the collective design experience and confidence of the folks in this thread. And while obviously it's not like this is a product to be sold and we need to think about thousands of DMs using it, it's certainly the case that this is intended to be used by DMs who can't do it themselves or we wouldn't need either explicit mechanics or guidelines.

I do not like the idea that monsters need a specified stat array with +1 bonuses every 4 levels like a PC, because attributes don't serve the same purpose for PCs & monsters. On PCs, attributes are a method of sharpening identities and encouraging certain overlaps in gameplay. On monsters, attributes are just a tuning lever. For the small percentage of the time that an earth elemental gets played as a PC, you can have a premade set of stat boosts written out as class features in your earth elemental class. Monster classes have done this for over a decade now without confusion, so it's a pretty safe bet.

I'm not saying to actually give all monsters the same stat array, I'm saying that if you're going to have tables of average-[whatever]-by-HD it should be based on the real numbers you get by doing things the long way, not just numbers pulled out of the Ethereal Plane with no relation to HD, ability scores, and so forth like 4e did. A simple note for each table along the lines of "The minimum, maximum, and average HP values in this table assume a d8 HD, a starting Con of 14, and an average of +1 Con per 6 levels" would suffice, so a new DM strictly following the table can give his 6-HD critter a 15 Con and be assured that all the math works out while someone more experienced can use that as a quick reference and then bump it up by 18 HP because he's giving his 6-HD critter a 20 Con instead.

The main thing here is the separation of creature types from HD and the stats that are derived from them is the primary goal. Having the more common monster chassises be refluffed into monster classes gives more uniform and easier to deal with customization for the DM, but trying to alter monster abilities into "monster class features" is a bit much for me. With exception of some of the more common abilities that could probably reworked into something akin class features, monsters in 3.5 are a bit too varied in their powers and abilities to be able to adequately account for most monsters.

"Monsters are too varied to systematize" is part of the problem that any monster class effort is trying to solve, you know. Whatever system we come up with shouldn't try to be slavishly backwards-compatible to the point that it can replicate a Dwarven Ancestor's +18 natural armor at 5 HD or an Adamantine Clockwork Horror's at-will disjunction and implosion at CR 9, it should result in a Dwarven Ancestor that's not everyone's go-to alter self form and an Adamantine Clockwork Horror that isn't a walking talking scuttling silent TPK waiting to happen.

[Just to Browse]

I think we agree on the importance of not rating individual abilities by CR, and the fact that these classes are more like designer training wheels rather than true PC classes. I'll only follow up on the stuff that I disagree w/you on.

Also, just for the purposes of keeping the language clear, since we're kind of using "class" interchangeable for a handful of things, I'd like to refer to these as:

• Your solution: pseudoclass, or maybe astral construct guideline (ACG)? (referring to the abilities that get called out at each level)
• My solution: pseudobuild, or maybe row based guideline (RBG)? (referring to the idea that you only read a single row of the table)
• The general idea of meatbags / masterminds / etc: monster guidelines
• A DM-approved ACG or a reverse-engineering RBG: monster class

The key thing for me is that the petrifying gaze shouldn't be available at 4 HD just because it's available at CR 4, because then you can make dumb 4-HD meatbags at CR 2 and so forth, and at some point you do reach a floor where a certain ability is inappropriate for monsters of a given CR. Granted, the boundaries are fuzzier at low levels since you can die or be removed from play for pretty much everything, but the principle gets to be more important at mid levels when a difference of a few points of CR or HD can mean the difference between "The party cleric has the removal spell for this condition, he can rest and have you fixed up tomorrow morning" and "We gotta go back to Waterdeep and spend a bunch of time and gold to get this taken care of."

If having 4 HD makes that encounter a more interesting experience for PCs then I don't have any problem with it. I can certainly imagine that an encounter with a basilisk guarding a treasure could be solved by scouting out the basilisk, sleep-bombing it, and walking around it. Some abilities are inappropriate at some CRs, sure, but we can already solve that problem by telling designers not to put petrifying gaze on creatures when if their CR < 4.

I didn't mean to imply that monster classes would literally be one feature every other level, just that those specific abilities would progress at those levels. I didn't write in any sort of "And at this level it gets something related to natural armor or energy resistance" since it wasn't germane to the example and might have led to bikeshedding.

This won't solve the problem, though. There is still an enormous delta between "NatArmor + ER + some stats" and "death gaze". Giant difficulty bumps are going to exist in your pseudoclass / ACG if CR 3-4 monsters have slowing gazes and CR 5-6 monsters have death gazes. Stat boosts rarely measure up to the kinds of encounter-altering abilities that puzzle monsters tend to have.

I'm down with your average designer being able to look over a list of 10-20 appropriate [monster type here] abilities and select the ones that they think fit best for the creature's CR. But the idea of generic features like DR or +Stats doesn't seem useful, because some of those are purely good for meatbags and others are purely good for masterminds. I see no value in giving designers the option of granting non-meatbag features to meatbags. I would simply rather see the relevant bonus stats baked into the meatbag class. More on this at the bottom of the my post.

The problem with that is that, quite frankly, most DMs are bad at designing custom opposition even within the normal system constraints, much less homebrewing something. Most DMs' first homebrew class or monster is terrible and unbalanced, most DMs' first BBEG is built like a player instead of like a good boss and either wrecks the party or dies like a chump, and most DMs are scared of letting random other peoples' homebrew into their games--even when that homebrew is by "known good" 'brewers and endorsed by people they know--because they're not confident in their ability to judge its balance.

No amount of guidelines that end up saying "...and then fiat something here, we're sure you've got this!" are going to turn out as well as hard mechanics that a new, uncertain, or just bad-at-design DM can follow explicitly, if only due to the fact that a single DM's design chops pale in comparison to the collective design experience and confidence of the folks in this thread. And while obviously it's not like this is a product to be sold and we need to think about thousands of DMs using it, it's certainly the case that this is intended to be used by DMs who can't do it themselves or we wouldn't need either explicit mechanics or guidelines.

Naturally, DMs will not make good homebrew in their first several goes, and should not be told to fiat things without guidance. I wrote as much several posts ago:

Guidelines can do this too. If you have a document that says "At level X, your monster should usually have features A, B, and C" and then there's a list of possible features, an inexperienced designer can follow those instructions. Monster design may even be easier for an inexperienced DM this way, because guideline tables can have rows like "Recommended Total HP" and "Recommended Save Bonus" which novices can copy/paste into a stat block instead of picking a Constitution score. Guidelines also make it easier to experiment, because now there is no mandate that Stone Gaze is a Menu C (level 6+ only) ability when a Basilisk with stone gaze is fine at CR 4.

An RBG can provide novice designers with the same kind of menu-based monster building experience that an ACG can. I believe that "DMs who can't do it themselves" can succeed without hard level-based guidelines, and I have even argued that they can do better when given a good alternative.

I'm not saying to actually give all monsters the same stat array, I'm saying that if you're going to have tables of average-[whatever]-by-HD it should be based on the real numbers you get by doing things the long way, not just numbers pulled out of the Ethereal Plane with no relation to HD, ability scores, and so forth like 4e did. A simple note for each table along the lines of "The minimum, maximum, and average HP values in this table assume a d8 HD, a starting Con of 14, and an average of +1 Con per 6 levels" would suffice, so a new DM strictly following the table can give his 6-HD critter a 15 Con and be assured that all the math works out while someone more experienced can use that as a quick reference and then bump it up by 18 HP because he's giving his 6-HD critter a 20 Con instead.

I think there is a lot of space between pulling something out the ethereal plane and locking attributes within tight bands. I believe the way we should handle monster attributes can fit comfortably between those 2 extremes. For example, here are various ways that monsters can get their HP-esque defenses:

• High Con
• Extra HD
• DR
• Fast Healing / Regeneration

Or any combination of those. A given monster guideline could suggest something like a Con score of 16 + (2 x CR) by itself, 15 + (1 x CR) with some DR or extra HD, or 12 + (1/2 * CR) with high fast healing. Novice designers can trust that the math works out, and experienced designers can experiment with different combinations. Like say a Kyton with 15 Con, but instead of high fast healing they get Regeneration 2 and DR 5/(silver or good).

[Durzan]

gonna give this thread a bump. I must say that I am enjoying the conversations in here quite a bit.

Unfortunately, I don't have much to say at the moment... keep it up!

[PairO'Dice Lost]

I think we agree on the importance of not rating individual abilities by CR, and the fact that these classes are more like designer training wheels rather than true PC classes. I'll only follow up on the stuff that I disagree w/you on.

Also, just for the purposes of keeping the language clear, since we're kind of using "class" interchangeable for a handful of things, I'd like to refer to these as:

• Your solution: pseudoclass, or maybe astral construct guideline (ACG)? (referring to the abilities that get called out at each level)
• My solution: pseudobuild, or maybe row based guideline (RBG)? (referring to the idea that you only read a single row of the table)
• The general idea of meatbags / masterminds / etc: monster guidelines
• A DM-approved ACG or a reverse-engineering RBG: monster class

That all looks reasonable.

This won't solve the problem, though. There is still an enormous delta between "NatArmor + ER + some stats" and "death gaze". [...] Stat boosts rarely measure up to the kinds of encounter-altering abilities that puzzle monsters tend to have.
[...]
I'm down with your average designer being able to look over a list of 10-20 appropriate [monster type here] abilities and select the ones that they think fit best for the creature's CR. But the idea of generic features like DR or +Stats doesn't seem useful, because some of those are purely good for meatbags and others are purely good for masterminds. I see no value in giving designers the option of granting non-meatbag features to meatbags. I would simply rather see the relevant bonus stats baked into the meatbag class.

Stat boosts and such aren't there to solve any sort of balance problem or somehow equal "bigger" abilities, they're there to make monsters more than just a cookie-cutter stat block with a single Puzzle mechanic, Artillery blast, or the like stapled on. There's nothing in the Medusa myth implying that medusas should have moderate natural armor, or that their snake venom necessarily has to attack Str instead of any other stat, but those things do make the encounter more interesting and give it more tactical considerations.

Plus, there are varying degrees of "encounter-altering." A climb speed or the (Cold) subtype are pretty irrelevant in the grand scheme of things and are the kinds of abilities that might be found on the not-signature-abilities-for-puzzle-monster-guidelines lists, for instance, but a basilisk that can chill on a ceiling to pop PCs when they walk through a door or a cockatrice that can hide in snowbanks so it's harder for PCs to run away from them make for a significantly different challenge.

I find it important to not only suggest those kinds of abilities but almost require them, because they can be a good source of inspiration when you're forced to think about them and because monsters can be fairly one-dimensional if they're left out. There's no particularly pressing reason for a shapeshifting infiltrator-type monster to have a tough hide, for instance, and in fact such monsters tend to be pretty squishy when their disguise is uncovered, but the Rakshasa's DR 15/good and piercing (or DR ∞/blessed crossbow bolt, in the olden days) is an excellent last-ditch defense and a great bit of lore.

And that goes for any sort of secondary ability that doesn't contribute to a monster's primary schtick, not just passive defenses. For instance, an Annis and a Green Hag both primarily wreck people in melee, but the Green Hag's Mimicry and various utility SLAs turn it from a straightforward bruiser into an ambush predator; those aren't the kind of things you'd find in a "here's things that make this creature a better Meatbag" list, but they flesh out its role nicely.

Giant difficulty bumps are going to exist in your pseudoclass / ACG if CR 3-4 monsters have slowing gazes and CR 5-6 monsters have death gazes.

Those kinds of difficulty bumps are always going to exist, because monster abilities advance roughly in line with spell level progressions and spells jump up in power every 2 levels. It's okay if no CR 12 monsters destroy your body when you kill you but a CR 13 Beholder can suddenly spam disintegrate rays and render you un-raise dead-able, for example, because resurrection can bring back a disintegrated creature and that comes online at CL 13, so a "normal" beholder fight at APL 13 can easily be cleaned up afterward by the party cleric and a "boss" beholder fight at APL 10 or so is scary but buying a scroll or hiring a cleric isn't out of their price range.

And of course not every pseudoclass is going to advance at the same rate. Meatbags really don't get anything new as they advance, just basic abilities to let them avoid getting one-shotted, while Masterminds, Fillers of the Outsider type, and any boss monsters are going to want a bunch of varied abilities, and other pseudoclasses are going to fall somewhere in between.

It's much like different spellcasting progressions, really. If a party fought nothing but classed NPCs for an entire campaign, any individual class of NPC would have noticeable jumps in power over time but no particular CR would be noticeably more dangerous than any other because classes all advance at different rates--barbarians are scary at level 1 when every greataxe crit is basically a save-or-die, bards are scary at level 2 when DFI + inspirational boost makes for very dangerous groups of mooks, wizards are scary at level 5 when they can snipe you with fireballs from 600 feet away, dread necromancers are scary at level 8 when they have hordes of boss-quality undead under their control, and so forth--so it doesn't matter so much when individual monsters have breakpoints as long as things are fairly even in aggregate.

I think there is a lot of space between pulling something out the ethereal plane and locking attributes within tight bands. I believe the way we should handle monster attributes can fit comfortably between those 2 extremes. For example, here are various ways that monsters can get their HP-esque defenses:

• High Con
• Extra HD
• DR
• Fast Healing / Regeneration

Or any combination of those. A given monster guideline could suggest something like a Con score of 16 + (2 x CR) by itself, 15 + (1 x CR) with some DR or extra HD, or 12 + (1/2 * CR) with high fast healing. Novice designers can trust that the math works out, and experienced designers can experiment with different combinations. Like say a Kyton with 15 Con, but instead of high fast healing they get Regeneration 2 and DR 5/(silver or good).

See, the thing I don't like about those sorts of guidelines is that they're basically begging the question. Anything that starts with CR in 3e or monster level in 4e and tries to calculate things from there is either going to end up highly inaccurate CR-wise if you can slap any ol' numbers or abilities onto that chassis or going to constrain the DM overmuch if you make them stick to that initial CR. (And the idea that HD and CR can diverge by more than 1 or maybe 2, à la 3e undead and constructs having a huge CR-HD disparity to make up for the lack of Con and thereby breaking all relative HD assumptions, is a terrible idea that should never have happened, but that's a separate issue.)

CR is a holistic measure that only makes sense to gauge once you have a completed monster in front of you. Saying you want to build, say, a CR 6 monster and so it should have this much HP is like saying you want to build a CR 6 NPC and so it should have 6 d8 hit dice--yeah, it's generally going to be in that ballpark, but both a Druid 6 and a Monk 6 have 6 d8 HD and the former punches well above CR 6 while the latter punches (ha) well below it, so starting there is backwards when it would make much more sense to build a Druid 6 or a Monk 6 and figure out how they measure up at CR 6 and whether you might need to make them a Druid 4 or a Monk 10 instead.

The pseudoclass approach to that sort of setup would be to instead define the number of HD first and make DR, fast healing, regeneration, and Con bonuses all things you can take at various levels. If you have two ability selections at a given level and can choose either "DR X and Con +Y" or "Con +Y, taken twice" that gives you a similar Con-for-DR tradeoff as the numbers you suggested; the differences are that (A) it doesn't pretend that a scaling Con bonus is linear in CR, as e.g. an extra +4 Con is huge at low levels and minor but still noticeable at high levels, (B) it maps much more readily to PCs taking monster classes since those advance by HD rather than CR, and (C) you don't have to be super-precise in balancing those individual options by CR, so the DM gets a little breathing room in how they fit together.

[Just to Browse]

Stat boosts and such aren't there to solve any sort of balance problem or somehow equal "bigger" abilities, they're there to make monsters more than just a cookie-cutter stat block with a single Puzzle mechanic, Artillery blast, or the like stapled on. There's nothing in the Medusa myth implying that medusas should have moderate natural armor, or that their snake venom necessarily has to attack Str instead of any other stat, but those things do make the encounter more interesting and give it more tactical considerations.

[...]

I agree that adding those sorts of features to a monster seem good. But I'm not in favor of the specific implementation. Namely, I do not want a "generic monster ability" list that includes things like DR or Con boosts. I would much rather have those broken apart per each monster guideline, because then you can appropriately budget the Rakshasa's DR 15/(good and piercing) without encouraging DMs to put 15 DR on a trap monster that is meant to die quickly, or on a meatbag monster that will only get frustrating with additional DR.

Those kinds of difficulty bumps are always going to exist, because monster abilities advance roughly in line with spell level progressions and spells jump up in power every 2 levels. It's okay if no CR 12 monsters destroy your body when you kill you but a CR 13 Beholder can suddenly spam disintegrate rays and render you un-raise dead-able, for example, because resurrection can bring back a disintegrated creature and that comes online at CL 13, so a "normal" beholder fight at APL 13 can easily be cleaned up afterward by the party cleric and a "boss" beholder fight at APL 10 or so is scary but buying a scroll or hiring a cleric isn't out of their price range.

[...]

I agree that a given monster class will likely have bumps in it, but monsters in general should not. For example, a CR 13 Beholder should not be significantly stronger than a CR 12 Roper just because a monster guideline says to do so. Monsters should be built around the idea that PCs power level will be "fairly even in aggregate", so monster guidelines need to reflect that.

See, the thing I don't like about those sorts of guidelines is that they're basically begging the question. Anything that starts with CR in 3e or monster level in 4e and tries to calculate things from there is either going to end up highly inaccurate CR-wise if you can slap any ol' numbers or abilities onto that chassis or going to constrain the DM overmuch if you make them stick to that initial CR. (And the idea that HD and CR can diverge by more than 1 or maybe 2, à la 3e undead and constructs having a huge CR-HD disparity to make up for the lack of Con and thereby breaking all relative HD assumptions, is a terrible idea that should never have happened, but that's a separate issue.)

[snip]

I'm not suggesting that any number can be thrown into the chassis. A monster's effective HP should be derived from the damage output of PCs at their level, because monsters are first & foremost encounters for PCs. The various combos of Con/DR, HD/Con, DR/Fast Healing should all be heavily mathhammered in order to achieve those effective HP numbers, which means that HP numbers aren't in danger of being inaccurate. This also doesn't restrict any options for monster designers: Novice designers immediately have multiple balanced pre-made stat blocks to choose from, and expert designers have examples that they can use for their own tinkering.

Your contrasting example showcases one of the problems with Con & DR being selectable features. Even if some values of DR x/- and Con +y are balanced compared to each other at a given level n (when an ACG grants a monster its bonus), that doesn't mean the same bonuses will be balanced compared to each other at level n + 5 or n + 10. And if we want to mix-and-match with something like Fast Healing, I'm not sure there are any values of DR x/-, Con +y, and Fast Healing z that exist, where the combinations (x, y), (y, z), and (x, z) are all balanced with each other.

In contrast, an RBG gives leeway for things like this. If a designer chooses Con + FH, the values can scale moderately by CR. If a designer chooses DR + FH, the values can scale poorly by CR. I believe that this sort of flexibility is only possible if you can isolate monster design on a single-row basis the way RBGs do.

To address your side note: Having HD diverge occasionally is totally fine, because high HD is a type of defense, and the game is more interesting if some monsters have that kind of defense. I do agree that systemically inflating HD is a bad idea, though.

Steps forward? @Pair, we've gone back & forth for a while, and I'm not sure we'll reach an agreement on any of these ideas in a timely manner. I also wouldn't mind taking a crack at actually writing out this RBG, given how much I have hyped up its miracles. Would you be interested in us both trying out our ideas and seeing how well they hold up? I'll gladly put a hold on responding to your next comment until we've finished the whole process.

If you are interested, I think elementals would be a decent choice for this kind of prototyping. The existing earth / air / water / fire elementals are supposed to scale but they're fairly mediocre across their entire level range, which gives us an opportunity to showcase how our solution can make them worth a DM's time. In the interest of this not being overly lengthy, we could try making a 10-row (or maybe only 5-row) RBG/ACG for 1 of the monster roles, and keep the number of options/level pretty low for now. Then we could use our tables to build some example elementals, and have some kind of design port-mortem.

[Durzan]

Gonna give this thread a bump.

[rferries]

I think I like the idea of total PC-monster transparency, along the lines of the old thread that tried to make all monsters LA+0.

In such a system monsters wouldn't have racial HD at all, just the most appropriate class e.g. an angel might just have cleric or favoured soul HD plus some feats for wings, a succubus might have levels of rogue plus feats for changing shape, a wolf might have a level of fighter and exchange weapon/armour proficiencies for feats granting natural attacks and scent, etc

This may be a lateral solution, but here's a repost of general monster abilities as feats I did a while ago:

Unless otherwise specified, all of the below feats can be taken as bonus fighter feats. They serve as viable prerequisites for other monstrous feats (e.g. Breath Weapon for Metabreath feats, Improved Grab for Multigrab, etc.).

Spoiler: Alternate Form

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Alternate Form
You can assume a different form.

Prerequisites
Character level 6th.

Benefits
You gain the Alternate Form supernatural special quality. You may use it to assume the form of specific creature of any type (chosen when you select this feat), with Hit Dice no greater than your character level. Your alternate form is as distinctive as your base form (e.g. it can be recognized by your enemies if encountered more than once).

Special
You may select this feat more than once, each time gaining an additional alternate form.

You gain the [Shapechanger] subtype.

Spoiler: Blindsense, Tremorsense, Blindsight

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Blindsense
You can almost see without sight.

Prerequisites
Blind-Fight or Wis 12.

Benefits
You gain blindsense out to 60 feet.

Tremorsense
The slightest vibration betrays the presence of your enemies.

Prerequisites
Blind-Fight or Wis 12, Blindsense.

Benefits
You gain tremorsense out to 60 feet.

Blindsight
You can see without sight.

Prerequisites
Blind-Fight or Wis 12, Blindsense, Tremorsense.

Benefits
You gain blindsight out to 60 feet.

Spoiler: Breath Weapon

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Breath Weapon
You can produce a mighty exhalation (or regurgitation).

Prerequisites
Endurance or Con 12.

Benefits
Once every 1d4 rounds you may unleash a breath weapon as a line or cone (chosen when you select this feat, of an area dependent on your size as shown below). All creatures in the area take 1d6 points of damage per two character levels, with a Reflex save for half damage (DC 10 + 1/2 your character level + your Constitution modifier).

Size	Line1 (Length)	Cone2 (Length)
Tiny	30 ft.	15 ft.
Small	40 ft.	20 ft.
Medium	60 ft.	30 ft.
Large	80 ft.	40 ft.
Huge	100 ft.	50 ft.
Gargantuan	120 ft.	60 ft.
Colossal	140 ft.	70 ft.

1. A line is always 5 feet high and 5 feet wide.
2. A cone is as high and wide as its length.

The breath weapon deals energy damage chosen from the options permitted according to your type or subtype, as shown below. Once you choose an energy type it cannot be changed, unless your type or subtype changes.

Type/Subtype	Energy Types
Any non-Undead	Acid, Sonic
Air	Cold, Electricity
Cold	Cold
Fire	Fire
Undead	Negative Energy
Water	Acid, Cold

The breath weapon is a supernatural ability, though a breath weapon of vomitus (acid) or yells (sonic) may be ruled an exceptional ability at the DM's option.

Special
If you are undead, the prerequisites for this feat and the saving throw DC of the breath weapon are Charisma-based instead of Constitution-based.

Spoiler: Change Shape

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Change Shape
You can infiltrate humanoid societies in a more pleasing form.

Prerequisites
Cha 12 or character level 1st.

Benefits
You gain the Change Shape supernatural special quality. You may use it to assume the form of any Small or Medium humanoid.

Special
You gain the [Shapechanger] subtype.

Spoiler: Damage Reduction, Improved Damage Reduction

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Damage Reduction
Your flesh deflects weapons or instantly heals wounds, unless magic is involved.

Prerequisites
Character level 1st.

Benefits
You gain damage reduction/magic equal to your character level.

Improved Damage Reduction
Your flesh can be harmed only by weapons of special materials or alignments.

Prerequisites
Character level 6th.

Benefits
You gain damage reduction equal to one-half your character level. This damage reduction is overcome by a special material of your choice (adamantine, cold iron, or silver), chosen when you select this feat.

Special
The damage reduction from this feat overlaps (does not stack) with the damage reduction from the Damage Reduction feat.

Spoiler: Disease

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Disease
You are a bringer of pestilence.

Prerequisites
At least one natural weapon.

Benefits
Your natural weapons inflict a disease, chosen when you select this feat. The disease has no incubation period and strikes instantly, unless your enemy is already infected with that particular disease. A successful Fortitude save (DC 10 + 1/2 your character level + your Constitution modifier) negates the disease or cures it on a subsequent save.

Special
You may not select demon fever for this feat unless you possess the [Evil] subtype and do NOT possess the [Lawful subtype.

You may not select devil chills for this feat unless you possess the [Evil] subtype and do NOT possess the [Chaotic] subtype.

You may not select mummy rot for this feat unless you are undead.

If you are undead, the saving throw against your disease is Charisma-based instead of Constitution-based.

You may select this feat more than once, each time selecting an additional disease.

Spoiler: Energy Drain

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Energy Drain
Your very touch brings death.

Prerequisites
Undead.

Benefits
Your natural weapons (including unarmed strikes) and any weapons you wield inflict a negative level with each successful attack. For each such negative level bestowed, you gain 5 temporary hit points.

Spoiler: Energy Resistance, Energy Immunity

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Energy Resistance
You are inured against a particular energy type.

Prerequisites
None.

Benefits
You gain resistance 10 to an energy type (acid, cold, electricity, fire, or sonic), chosen when you take this feat. This resistance increases to 20 at character level 5th and to 30 at character level 9th, and stacks with all other sources of energy resistance.

Special
You may select this feat more than once, each time gaining resistance to a different energy type.

Energy Immunity
You are unharmed by certain energy types.

Prerequisites
Energy Resistance.

Benefits
You gain immunity to all energy types for which you selected Energy Resistance.

Spoiler: Energy Subtype

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Energy Subtype
You are infused with a particular energy type.

Prerequisites
None.

Benefits
You gain the cold subtype or the fire subtype. You gain immunity to energy of the chosen subtype, and vulnerability to energy of the opposing type.

Special
You may select this feat twice, gaining immunity to both energy types.

Spoiler: Extra Limb

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Extra Limb
You have an extra limb - acquired at birth, through a magical mishap, or some other means.

Prerequisites
Base attack bonus +1.

Benefits
You gain an additional limb, either an arm or a leg.

If the extra limb is a leg your base land speed increases by +10 ft.

If the extra limb is an arm, you may use it to wield a weapon, bear a shield, and so forth.

Special
You may select this feat more than once, gaining an additional limb each time.

If you have at least three arms, you qualify for Multiweapon fighting and similar feats. Any Two-Weapon Fighting feats you have already selected are replaced with the appropriate Multiweapon equivalents.

The benefits of the Natural Weapon feat apply both to your base limbs and any limbs f the same type that you gain through this feat.

You may use this feat to gain a limb of non-humanoid anatomy (e.g. a tentacle, tail, wing, etc.). Simply treat this limb as either an arm or a leg, save that you can gain new types of natural weapons with it via the Natural Weapons feat.

Spoiler: Fast Healing, Regeneration

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Fast Healing
You heal rapidly.

Prerequisites
Character level 6th.

Benefits
You gain fast healing equal to one-half your character level.

Regeneration
You are very difficult to kill.

Prerequisites
Fast Healing, character level 12th.

Benefits
You gain regeneration 0, overcome by acid and fire attacks. This works exactly as standard regeneration, save that you do not regain any hit points each round (other than those from your Fast Healing feat).

If you lose a limb or body part (including your head), the lost portion regrows in 3d6 minutes. You can reattach the severed member instantly by holding it to the stump.

Special
If you acquire immunity to both acid and fire, your character transforms into Pun-Pun and ascends to a higher plane, never to return (roll a new character).

You are not immune to the nonlethal damage inflicted by this feat (even if you are undead or otherwise immune to nonlethal damage).

Spoiler: Fear Aura

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Fear Aura
Your presence inspires terror.

Prerequisites
Character level 6th.

Benefits
All enemies within 30 feet of you must make a Will save (DC 10 + 1/2 your character level + your Charisma modifier) each round or become shaken. This stacks as normal for fear effects, up to panicked. This is a supernatural necromantic fear effect. You may suppress or reactivate this ability as a free action.

Special
If you have ranks in Intimidate, the save against your fear aura increases to 10 + your ranks in Intimidate + your Charisma modifier + any other bonuses toyour Intimidate checks (e.g. from the Persuasive feat).

Spoiler: Gaze

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Gaze
Your gaze is as deadly as that of the medusae.

Prerequisites
Character level 12th.

Benefits
All creatures (including allies) within 30 feet of you that meet your gaze must make a Fortitude save (DC 10 + 1/2 your character level + your Charisma modifier) each round or be turned to stone. This is a supernatural gaze attack. You may suppress or reactivate this ability as a free action.

Spoiler: Improved Grab, Constrict, Rake, Swallow Whole

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Improved Grab
You can seize and grapple foes with ease.

Prerequisites
Base attack bonus +1.

Benefits
You gain the Improved Grab special attack for all your natural weapons (including unarmed strikes). Whenever you hit an opponent with a natural weapon, you can then attempt to start a grapple as a free action without provoking an attack of opportunity. If you win the grapple check, you establish a hold and can constrict and/or rake (if you possess those special attacks).

Special
You may benefit from this feat while grappling a creature regardless of your relative sizes.

This feat replaces Improved Grapple.

Constrict
Your grapples crush your foes.

Prerequisites
Improved Grab.

Benefits
You deal double damage on a successful grapple check with a natural weapon (including unarmed strikes).

Rake
Your grapples shred your foes.

Prerequisites
Improved Grab, at least two natural attacks.

Benefits
If you start your turn grappling a creature, you may attack that creature with all your natural weapons (except any being used to conduct the grapple). These attacks are not subject to the usual -4 penalty for attacking with a natural weapon in a grapple.

Swallow Whole
You can devour your foes whole.

Prerequisites
Improved Grab, bite natural weapon.

Benefits
If you start your turn with an opponent held with your bite (see Improved Grab), you can attempt a new grapple check (as though attempting to pin the opponent). If you succeed, you swallow your prey, and the opponent takes bite damage.

You may swallow one opponent at least one size category smaller than yourself, two creatures at least two size categories smaller than yourself, four creatures at least three size categories smaller than yourself, and so forth. You may swallow combinations of creatures e.g. one creature two sizes smaller than yourself and two creatures three size categories smaller than yourself.

A swallowed creature is considered to be grappled, but you are not.

A swallowed creature can try to cut its way free with any light slashing or piercing weapon by dealing damage equal to your Constitution score, or it can just try to escape the grapple. The Armor Class of your interior is 10 + ½ your natural armor bonus (if any). If the creature cuts its way out, you take no damage and muscular action closes the hole. If the swallowed creature escapes the grapple, success puts it back in your mouth, where it may be bitten or swallowed again.

For each round that a creature that does not escape your stomach, it takes bludgeoning damage equal to your bite damage plus acid damage equal to your Constitution modifier.

Special
If you possess the Breath Weapon feat, a swallowed creature takes damage of your breath weapon's energy type in equal to the acid damage it takes (or double acid damage if your breath weapon deal acid damage).

If you are undead, replace all references to Constitution in this feat with Charisma.

Spoiler: Keen Senses

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Keen Senses
You are as perceptive as a creature of the wilderness.

Prerequisites
None.

Benefits
You gain darkvision out to 60 feet, low-light vision, and scent. If you already possessed any of those abilities, their ranges are doubled.

Spoiler: Movement Mode

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Movement Mode
You can move in an inhuman manner.

Prerequisites
Character level 3rd or 6th (see below).

Benefits
You gain a climb speed equal to your base land speed, or a swim speed equal to twice your base land speed. In either case you gain a +8 racial bonus on the appropriate skill check (Climb or Swim) and may always take 10 on that check, even if rushed or threatened.

If you are at least 6th level when you take this feat, you may instead choose to gain a burrow speed equal to your base land speed, or a fly speed equal to twice your base land speed (good maneuverability).

Special
At the DM's option, you also gain the Aquatic subtype and Amphibious special quality if you gain a swim speed with this feat.

You may select this feat more than once, each time gaining a new movement mode.

Spoiler: Natural Armour

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Natural Armour
Your hide is as tough as armour.

Prerequisites
Character level 6th.

Benefits
Your natural armour bonus increases by one-quarter your character level (a creature without natural armour that selects this feat has a natural armour bonus of +0).

Special
You may select this feat more than once. Its effects stack.

Spoiler: Natural Weapons

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Natural Weapons
You possess mighty weapons even when unarmed.

Prerequisites
Base attack bonus +1.

Benefits
Choose a natural weapon from the table below. You gain a natural weapon of that type for each corresponding body part you possess.

Natural Weapon	Body Part
Bite	Mouth
Claw, Hoof, Pincers, Slam, Talons, Tentacle	Hand, Foot
Gore	Horns
Wing	Wing
Sting, Tail Slap	Tail

The natural weapons are primary attacks that deal damage according to your size (or according to your unarmed strike damage, if you are a monk). If you are attacking with manufactured weapons, the natural weapons are treated as secondary attacks during a full attack. Any limb currently wielding a weapon, bearing a shield, or otherwise occupied cannot be used to make a natural attack.

Special
You may select this feat more than once, each time gaining a new type of natural weapon (e.g. a humanoid typically has one mouth, allowing for one bite attack; the same humanoid typically has two upper limbs, allowing for two slams or claw attacks).

The same body part may not be selected more than once for this feat (e.g. you may use your hands for claws or slams but not both, though you might use your hands as claws as your feet as slams).

Spoiler: Nonability

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Nonability
You are either lifeless or mindless.

Prerequisites
Character level 6th.

Benefits
You lose either your Constitution score or your Intelligence score.

If you lose your Constitution score, you have no metabolism. You do not need to sleep, eat or breathe. You are immune to any effect that requires a Fortitude save unless the effect works on objects or is harmless (in which case you automatically fail the save). You are also immune to ability damage, ability drain, and energy drain, and automatically fail Constitution checks. You cannot tire and thus can run indefinitely without tiring. Your Constitution modifier is 0 for all purposes (including bonus hit points per Hit Die). You cannot heal or be healed, except through the Fast Healing special quality. Your type does not change.

If you lose your Intelligence score you are mindless, an automaton operating on simple instincts or programmed instructions. You have immunity to mind-affecting effects (charms, compulsions, phantasms, patterns, and morale effects) and automatically fail Intelligence checks. Unlike other mindless creatures you retain your feats and skills, though you are rarely able to use them. You are unable to use Charisma-based skills, cast spells, understand language, or communicate coherently. Still, you know who your friends are and can follow them and even protect them.

Special
You may select this feat twice, losing both ability scores.

If you lose your Constitution score, you count as an undead creature for the purpose of [Monstrous] feats.

Spoiler: Poison

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Poison
Your natural weapons inject a virulent venom.

Prerequisites
At least one bite or stinger natural weapon.

Benefits
Your bite and stinger natural weapons inflict a poison that deals initial and secondary ability damage equal to the base weapon damage, according to your size. The damage is Constitution, Dexterity, or Strength damage, chosen when you select this feat. A successful Fortitude save (DC 10 + 1/2 your character level + your Constitution modifier) negates the damage each time.

If you possess both bite and stinger natural weapons, the poison is delivered through both of them.

Special
If you are undead, the saving throw against your poison is Charisma-based instead of Constitution-base.

You may select this feat more than once, each time selecting an additional type of ability damage to deal with your poison (either the same type or a new one). The effects stack.

Spoiler: Pounce

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Pounce
Your charges are lightning-fast.

Prerequisites
Base attack bonus +1.

Benefits
When you charge a foe, you can make a full attack.

Spoiler: Powerful Charge

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Powerful Charge
Your charges are brutally strong.

Prerequisites
Base attack bonus +1.

Benefits
When you charge a foe, all attacks you make that round deal double damage.

Spoiler: Spell Resistance

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Spell Resistance
Through special training, prior magical exposure, or sheer force of will, you have gained some measure of resistance to spells.

Prerequisites
Character level 3rd.

Benefit
You gain spell resistance equal to your character level +5. At 6th level this improves to your character level +10. At 12th level this improves further to your character level +15.

Spoiler: To Do

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To Do
Balance the prerequisites! Typically set them to a character level at which spellcasters can cast equivalent spells; perhaps Intimidate as a Fear Aura prereq, Climb/Swim as a Movement Mode prereq, etc.

Rework Natural Weapons - e.g. a separate chain for Wing Attacks & Flight.

Blood Drain (as weasel, vampire, etc)

Etherealness, Incorporeality (as phase spiders, spectres, etc.)

Gaseous Form (as ogre mage, vampire)

Gaze attacks (other options e.g. bodak, spirit naga)

Invisibility (as pixie, will-o'-wisp)

Magic Immunity (as golems)

Monstrous Defenses (e.g. immunity to poison, sleep, disease, etc. by type or as demons, unicorns, etc are)

Rend

Summon (as demon)

Telepathy

Trample

Turn Resistance

[Bohandas]

How do we separate monster type from HD and all other similarly dependent stats?

I think the thing to do here is just do it. Assign new HD, BAB, saves, skill points, etc. independently of each other and in accordance with what fits the monster