Ability Modifiers & Target Numbers (2024)

One of the unique things in TNP is that the system does not use ability scores, or derived ability modifiers. When I was first learning D&D (with 3.5e) I couldn't wrap my head around the way that you got these numbers. As I've kept up with the game over the years, I eventually picked up on how it works... but the game also has slid into more of a "paint by numbers" sort of ethos, as far as ability mods are concerned.

The example I gave in an earlier post lays out this idea pretty succinctly. Essentially, if your attacking stat's modifier is assumed to be +3 and your starting proficiency bonus is +2 (such as in 5e D&D) then you should be able to hit a fairly-baseline AC of 15 about 55% of the time. The same is true if you just ditch the +5 modifier, and roll against a 10 AC. This is the nature of the 'flat math' provided by using d20 mechanics. By keeping the target number as a consistent 10, TNP dispenses with those minor 5%-10% deviations you get from not painting by numbers properly. It also means that enemies will always be an appropriate challenge (assuming damage and HP math is correctly mapped and implemented) but doesn't really allow for that flexibility to gain minor advantages in combat.

For example, with 4e effectively having 4 defenses (AC, Fortitude, Reflex, and Will) some characters could kit themselves out such that they could always target more than one of these, narrowing in on an enemy's weakness in any given battle. There were even feats such as Lightning Rush, which (if memory serves) let your charge attacks target Reflex rather than AC; the issue I take with this is that, by and large, it's "just another +2" by a different name. (As per "monster manual 3" math, AC was typically 2 points higher than the other defenses.)

The problem with ability scores and ability modifiers, is that they have become outdated. Class features do more to determine your character than anything else, and we've outgrown the era where the 6 stats were all you needed to run your character. They also end up pigeonholing which skills you're good at, based on the necessity of cranking up whichever ability you use for combat (or other class features.) In my previous RPG designs, this is why the "attributes" were literally described as just being the numbers that your mechanics and stats derive from; they weren't based on physical or mental prowess, and the combat applications of those numbers were not coupled to your non-combat skills.

Even when it comes to damage, ability modifiers have a similar effect to how they impact the d20; they increase the floor and the ceiling in a linear fashion, but don't actually push bad rolls "off the table" (so to speak.) This is why I preferred a mechanic such as mastery, over just endlessly stacking flat modifiers. But looking back on my older designs, I do find myself having a greater appreciation for some of the upsides of using flat modifiers -- rather than leaving every mechanic up to some interpretation of the dice, as in TNP. However, another issue with the d20 ethos is that a +1 to hit translates to a lot more average damage than a +1 to damage.

The more I consider the possibility of designing another game after TNP, the more things such as this crop up, as examples of where I should figure out a way to "square the circle." TNP doesn't use flat damage modifiers (or attack modifiers) or additional [W] expressions (as 4e does) to beef up damage, so the perceived "elegance" of d20+class dice ends up losing its lustre -- because so many extra things need to be piled on, to make the math work. I feel like the correct dose of flat modifiers could help alleviate some of this, but I'm also sort of honing in on the idea of keeping d6 and d10 as the extra damage dice, and limiting their other uses (at least as far as combat and/or 'class die' applications.) It'll be interesting to see where things go, in the future.

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Next post should be May 15th, so check back then!

Apples & Oranges (2024)

One of the gripes I have with the design of 5e is how incongruous it is.

The example that immediately jumps off the page to me is how armor progression is essentially attribute-based for light armor users (or unarmored builds), but is money/loot-based for heavy armor users. Would it be so undesirable to just have heavy armor AC improve with STR, the way light armor AC improves with DEX?

Likewise, I find this same problem when you compare (for example) an archery Fighter build vs. a Warlock eldritch blast build. Right off the bat, the Fighter has the clear advantage, from being able to take a +2 to hit with their fighting style, and already adding +DEX to ranged weapon damage -- whereas the Warlock needs to spend "class feature currency" to gain +CHA to their eldrtich blast damage, and no comparable way to increase their hit chance.

Where the Warlock pulls ahead, is the fact that they deal force damage right out of the gate; again, the ability to deal "magical" weapon damage, or non-mundane types of damage as a Fighter comes down to loot... which in itself either comes down to plot contrivance (in the case of a published adventure) or outright DM fiat. At levels where resistance to mundane weapon damage becomes more ubiquitous, a Fighter without an appropriate magical weapon will see their damage fall off substanstially.

The odd thing about it is, the solution is already in the game, in other places; as a 6th level Monk, "your unarmed strikes count as magical for the purpose of overcoming resistance and immunity to nonmagical attacks and damage." A rogue with the Soulknife archetype can deal psychic damage basically at will, from 3rd level. Likewise for Paladins, "By 11th level [...] Whenever you hit a creature with a melee weapon, the creature takes an extra 1d8 radiant damage" in addition to the push-button radiant damage they can do with Divine Smite, or other types of magical damage they can deal with their buff spells. It's also pretty easy for Wizards or Sorcerers to have at least two different "flavours" of damage from their cantrips alone.

The question I find myself asking is, what is the point of this type of design?
We saw some steps forward with 4e, such as making sneak attack not care about the anatomy of your target in order for it to work. And the distinction between piercing/bludgeoning/slashing weapons had more to do with qualifying for feats than resistance/immunity. But at later levels, this cat-and-mouse game started to creep in, where ongoing damage started at 5 and resistance started at 3, with both scaling up over the tiers of play. We also see this kind of thing in Diablo 2, where after a certain point in the patch history, all paladins became spellcasters because dealing magical damage was more effective than buffing your sword swings -- and that's to say nothing of the fact that Diablo games are fundamentally about gathering more and better loot, whereas (in my opinion) D&D should not be.

I guess at the core of my meanderings is this opinion: it doesn't work. Designing some classes (and their progression) around their attributes and class features, while others are effectively designed around the loot they find...? It doesn't work for TTRPGs. You need to pick a lane in terms of your designs, and stick with it; if a class fundamentally can't function without specific loot or gear, then those items need to be made into class features instead. And if you're going to build a resistance/immunity mini-game into your combat, it's probably best done as a mechanism by which you allow one party member to shine; the double-edged sword with that is you essentially pigeon-hole your designs around the assumption that all parties must be composed a certain way, or there will be enemies they either can't win against, or will struggle a lot harder to deal with.

This is why TNP has always been built around the concept that "all damage is created equal." This helps with a lot of the abstraction, including things like base damage dice; whether a Fighter is dealing 1d6 damage with a shortsword or a quarterstaff or a scimitar is irrelevant. When looking back at my previous designs, added damage types created additional effects, such as poison damage ignoring damage reduction from armor, or cold damage causing penalties to speed and initiative; I think this is a lot better way to handle this sort of concept, within a table-top setting.

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Next post is due up on May 5th, so check back then for more!

Filling the Toolbox (2024)

When setting out to build the mechanics of a game, I think it's important to figure out what things you want to emulate and what not to emulate.

To give an example, the 3.5/4e paradigm of using flanking to provide a +2 attack bonus (referred to as Combat Advantage, in 4e) placed an emphasis not only on precise positioning and grid-based combat, but also a focus on tactics, co-operation, and teamwork. Without this as a baseline rule in 5th Edition, sources of advantage or other dice bonuses more or less boil down to "magic did it."

When I started off working on TNP, I always sort of envisioned a system where "playing to type" would give you advantage on the action you were taking; the easiest example I can put forward would be attacking in melee as a barbarian. This ethos could also be applied to something like which skills you use; to wit, earlier versions used class dice for the skill mechanics, and some of those included replacing d6s with bigger class dice for skills that were "iconic" to a given class.

Along with advantage/disadvantage, I had always envisioned expertise/mastery as being the signature, cornerstone dice mechanic that TNP would operate off of -- but in actuality, class dice ended up being its own layer of class-specific mechanics (particularly when it came to attack rolls.) In the recent drafts, the decision was made to standardize the class dice mechanics; a d4 bonus granted by a Cleric would be the same as a d4 bonus granted by an Acrobat, or a Druid, or a Sage, etc.

This is also around the time I started to ask a question, what really are the core dice mechanics of the system? Part of what created this impetus was the decision to move away from d20 for skills. What came out of this question was the 5 core rolls (attacks, saves, skill checks, initiative checks, and base damage) and the more standardized, streamlined bonuses that applied to them (attack bonus, save bonus, skill rank bonus, initiative bonus, and extra damage.)

Another aspect of "filling the toolbox" with regards to the game's mechanics was the skill grid. I've mentioned it before, but essentially, between the core skills (aka ACIDS tests) and knowledge skills, TNP pretty much covers all of the skills included in D&D, from 3.5 onward. Not to say that I necessarily think all of those skills will be used in every campaign, but by fitting them all somewhere into the grid, you can bolt the skill system (even, potentially, without bolting the rest of TNP) onto a game or an adventure where all of those skills are assumed to be part of the designs.

One thought I've had as it pertains to the skills grid is the idea of how it could be implemented differently. For example, in an ethos where "ability modifiers" are kept to a minimum of +1, you could easily substitute those numbers for your skill ranks, with each +1 bonus adding another d6 to the dice pool; if attributes determine skill rank bonuses, then the implication would be that skill "training" (i.e. advantage on the d10 component) would be a function purely of skillsets, rather than being applicable to skillsets or attributes (as it currently is.) This would actually be an interesting way of doing things, particularly in a potential "2d6" DC10 system, described in a previous post.

I think the other big bit of "toolkit-building" in TNP relates to the status effects and conditions. I actually have already made a quite lengthy post on the decision process behind which ones to include, so I won't rehash all of that here. What I will say, is that I think perhaps these designs are a bit "over-engineered," for purpose. It may very well be that this serves as the baseline for a new system, since I keep finding myself rarely incorporating these deeply into the character class designs, any time I do a re-draft. 

Part of that is because I think of TNP as being designed more as an "HP attrition" game first and foremost. A lot of the optimization mentality in 4e was that debilities just drag out the (already lengthy) combat, essentially forcing the party to spend more resources (particularly healing resources) whereas building around higher damage helps to more quickly advance combat to its natural end-state. "Damage is king," as they say. Circling back around to what I said earlier in the post, playing to type was meant to make your character more effective (i.e. deal more damage) in combat.

The other part of it is as a response to 5e having such poorly-designed and under-utilized conditions. To wit, seemingly every spell has its own conditions, and if a spell does reference one or more of the pre-established conditions, it always builds some clunky exception(s) into it. Much like standardizing the class dice bonuses, I wanted TNP to have standardized conditions, which do the things you expect things to do, in a D&D game. To this point, while I think the 4e conditions are sometimes very "gamey" and don't always lend themselves to this ethos, I think the format and the standardization of 4e's conditions laid a good foundation for how this sort of thing ought to be done -- and that's why TNP apes this formatting so closely.

If there's one more idea I'd include in this exercise, it's the mechanics of the monster roll. As I've mentioned before, one thing I did when homebrewing monsters in 4e, was to standardize the damage expression -- rather than having each subtype of each monster race using different types of dice. The fact that the MM3 math was so standardized, made this sort of thing easy to reverse-engineer. Part of the monster-building "toolkit" is this idea of having a standardized damage dice roll, regardless of the monster type. Part of the thinking behind "using the dice for everything" in TNP (rather than having static modifiers) is that it creates a stable cap on what damage expressions can potentially be -- and nowhere is this truer than with the monster mechanics; each swing is only ever going to be 1d10+1d6, with standard monsters only using the higher die, effectively capping them at 10 damage, while elites, solos, and archenemy types are capped at 16 (albeit solos and archenemies will likely take more than one swing per round, or have access to multi-target abilities.) With the HP for PCs varying between 24 and 32, this also gives us a pretty good handle on what combat length should look like, once we account for "save" chance and come up with DPR expectations for monsters.

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A bit of a retrospective post today, but I'm also thinking of how I can move things like the mechanics forward, into future designs. So I find these little exercises in navel-gazing to be occasionally helpful.

Next post is due up on April 24th, so check back then!

Campaign Scaling (2024)

As I've recently been giving some thought to HP and reserves, the idea of doing a 'basic' and an 'advanced' version of TNP has recently popped into my head... but we'll shelve that discussion for now. A lot of the numbers for these player statistics are essentially built off of using the dice to generate values similar to those in 4e D&D, when it might be more practical to just scale things down -- say, by using a flat 10 for HP and also for reserves.

The problem that this bumps into is how reserves scale over levels, and this dovetails into a broader design discussion, which I haven't really brought up on the blog before.

In my experience, there are essentially two different ways to scale up player power in RPGs: either the PCs get stronger, and enemies stay relatively static, or the PCs get stronger while the enemies also get stronger. I would say the latter describes the previously mentioned "MM3 on a business card" ethos for 4e D&D; if your chance to hit goes up by +1 every level, but your enemies' defense also goes up by +1, then the relative math stays about the same (assuming a d20 system.) This is what I often (uncharitably) refer to as "the illusion of progress," because while your numbers go up, your ability to hit remains mostly unchanged. The flexibility of this method is that when you fight enemies of considerably lower level, the PCs should be able to absolutely dunk on them; the question that arises is whether or not this is a valuable metric, or if the challenges the PCs face should always remain relatively equal to their level.

The drawback to the alternative method is that you end up with a system where the game starts off hard, but as the PCs become more powerful, the game unintuitively becomes easier. The proper way to execute this idea is to make the opponents more challenging in other ways (generally, AoE or multi-attack, or other similar 'action economy' advantages) but this requires a great deal of mathematical crunch, to get just right. It also means gating more difficult enemies to higher levels.

The circle which I am trying to square with TNP is how the reserves per day mechanic should be handled. The skeleton idea for the card-based random campaign generation system would essentially proscribe that at starting level you would have 4 encounters, and at your final level, you would have 14 (half of which statistically would be combat encounters.) So, if the idea is that you would need to spend 1 reserve to heal up from each combat, then you only need to spend 2 reserves at your starting level, but 7 reserves at your final level. This is an inversion of the previous example, since the PCs are starting out with more than enough reserves, but at later levels they are going to be riding a fine line; whereas the expectation is that the PCs would get stronger (even though the enemies might get stronger, too) in TNP they're getting relatively weaker, since all other math is kept flat (attack, damage, HP, etc.)

What ends up happening with "reserves based on max value of class dice" is that the range of numbers has quite a bit of variance (from 4 to 12.) Using two class dice for 10 of the 15 classes helps with this, but to really mitigate the variance, we need to raise the floor for the other 5 classes -- essentially, by raising d4 and d6 to "2d4" and "2d6" when it comes to reserves. This gives us a variance between 8 and 12.

So, this begs a few questions: does the minimum need to be 8? Or is 6 enough (if the highest average number of combat encounters per day is expected to be 7)? If the variance is as small as 8 to 12, wouldn't it make sense to do something like say "everyone gets 10, period, end of story," and just save all the useless overhead? Well, for a 'basic' version, I would argue absolutely it makes sense... and sometimes what's good for the goose is good for the gander.

This is where we circle back to the idea of "reserve burning" abilities. For the sake of argument, let's say that 8 is considered to be the minimum number of reserves needed, just to get by with healing. What this essentially does (by implication) is make "d10 reserve" classes into the ones that should get 1/day reserve-burning mechanics, whereas the "d12 reserve" and/or "2d6 reserve" classes end up with the 1/encounter reserve-burning mechanics. So how would this shake out in practical terms?

Cleric (d4/d10) = 8 or 10
Fighter (d6/d12) = 12
Acrobat (d4/d8) = 8
Paladin (d6/d10) = 10 or 12
Warlord (d8/d12) = 8 or 12

Druid (d4/d12) = 8 or 12
Guardian (d4/d6) = 8 or 12
Adventurer (d6/d8) = 8 or 12
Ranger (d8/d10) = 8 or 10
Barbarian (d10/d12) = 10 or 12

If we reverse-engineer the numbers a little bit, this essentially means that any d10 class either needs to be a tankier class (expected to burn through more healing than average) or needs to have a 1/day ability; d12/2d6 classes need to be both tankier AND have a 1/day ability, OR they need to have a 1/encounter ability. It makes for some potentially interesting added design space, but it doesn't always line up smoothly. The interesting thing is that since most classes could potentially operate off of two different numbers of reserves, this also makes it possible for each subclass within a class to have some variance w/r/t reserve-burning mechanics. The trick of it is to not bump at-will abilities to being per-encounter abilities, simply because we can give a class enough reserves to do so.

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Next post is due on April 14th, so check back then!

Core Designs: "Players Always Roll" (2024)

In the earliest iterations of TNP, the idea was that monsters would always do a flat amount of damage (usually 1 point) when they targeted the PCs. This was partly because HP was a lot lower (essentially capped at "maximum value of your class die") but was also done to speed up gameplay; it was one less roll the GM needed to make. When I decided to expand the monster roster to include minion types (and swarms) this idea of fixed damage was integrated into their designs, and other monsters were given a damage roll, often referred to as the "monster roll" -- specifically a d10 and a d6.

(Without going on too much of a derail, this was derived from my own hack of the "MM3 on a business card"-math that came out of 4th Edition D&D; essentially, I used 1d6+1d10 (per tier) as the monster's damage roll.)

In 4e, the ethos is "attacker always rolls" i.e. you don't roll a Reflex save when targeted, instead the attacker rolls vs. your Reflex defense to determine whether their attack succeeds. TNP kind of... does an homage to this, by saying "players always roll," which means you roll if you're attacking OR if you're being attacked. This was an interesting quality-of-life improvement on the DM side, particularly in the play-by-post playtest games I've done; the DM could declare the monsters as targeting certain PCs, and say, "roll defense; take X damage on a fail," and the play could move on to the next person in initiative. Eventually the roll made when a player was attacked got renamed from a "Defense roll" to the more familiar "saving throw." 

Where this tends to get gummed up is in status effects and conditions. For example, if an effect gives you disadvantage on attack rolls and saving throws (such as the Incapacitated condition) how does that work for monsters, who don't make either? Well, the short explanation is that while the monster roll funcions as the damage roll (on a failed saving throw) it is treated as also being the monster's "attack roll" for the purposes of applying such penalties; the disadvantage is applied to the d10, thus making the monster roll effectively a "percentile" die roll which models advantage/disadvantage, and with a d6 added to it.

(Worth mentioning here is that this is also how skill checks are handled, as they use the exact same dice. In the new draft I have been working on, skill checks are therefore recommended to always be rolled as percentile dice with a d6 bonus die, rather than "1d10+1d6" -- but more on that in a future post, probably.)

Alright, so what about the disadvantage on saving throws? Well, the Incapacitated condition (which gets nested into lots of other debilities) also causes anyone with this condition to grant combat mastery to their enemies. Now, this is where I need to have a big think: Should the condition expressly say, "monsters are impacted in X way, but PCs are impacted in Y way," or, should this condition cause PCs to both have disadvantage on saving throws and grant combat mastery, while monsters only do the latter? This seems overly-punishing in a way that isn't really intended, so I'm thinking some of these conditions might have to stipulate different effects for monsters or players.

The same issue arises with things like positioning or terrain effects; since "advantage on saving throws" has been excised from the mechanics, these effects instead grant the PCs a save bonus (a d6, which can be stacked, but only the highest d6 roll is kept.) But what about the monsters? Well, they don't make saving throws, so instead the PCs should have disadvantage to attack enemies with one or more of these effects in play... Which then begs the question: Instead of a save bonus to the PCs, should cover (or similar) instead grant disadvantage on the monster's "attack" roll, just so that the terminology being used is consistent (even though the mechanical applications are different)?

I do think that the way in which conditions and status effects were built out in 4e was slick, and very much worth emulating. I'm just having a bit of trouble translating that ethos over to a system with a different mechanical underpinning. This is one of the other reasons that I'm becoming more convinced I'll want to take on the task of doing a followup game to TNP. I think the game could be made to run a lot smoother with some different mechanical underpinnings, such as "attacker always rolls" and using things like flat modifiers in some places (instead of dice, for everything) -- but then it wouldn't be TNP anymore; it'd necessarily have to be something different.

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Next post is planned for April 4th so check back then!

Basic Bookkeeping (2024)

Part of the design ethos that went into the 2021 draft was to use class dice as sort of a "keyword" for certain character statistics, but also to bind some of these stats together.

For example, "reserves & surging" were treated as a paired set of statistics, but this produced some odd results. The 1d4 class die "expression" translated to 8 reserves and a surge value of 4, with 1d6 producing 6 and 12, respectively. On some of the classes that were updated most recently (Druid being the one that comes to mind) some expressions were de-coupled, in order to make these statistics operate more smoothly.

I think part of the reasoning for pairing the stats together in the first place was so that there were fewer expressions you needed to remember; if your class has two class dice, then you'd only ever need to memorize two class die "expressions" -- making it so there was a 50/50 chance that you'd be able to guess which value to use, if you couldn't remember. That sort of falls apart when sometimes 1d4 means 4 and sometimes it means 8, as mentioned in the example.

It also didn't really manage to facilitate what it was meant to do, within the design ethos (namely, to raise the floor on certain numbers.) These expressions being unituitive just meant that their functions ended up needing to be spelled out on each class loadout anyway, or else you'd have to refer back to the core rules that explained the values these expressions were meant to generate. In other words, something that was meant to speed things up and streamline the jargon, actually seems to have made things less clear, not more.

This all sort of highlights the limitations of the overall TNP design ethos, whereby "all of the numbers have to derive from the (class) dice," but also highlights how the added flexibility of using a 2nd class die is so important... or at least helpful.

Pivot Point
Since HP in the current versions is calculated as the maximum value of your initiative check (including initiative bonus) HP and initiative bonus will necessarily continue to be paired together. However, I don't think that there's necessarily any benefit to keeping your engagement value coupled with your initiative bonus, as was the case previously.

The idea that I'm moving forward with is that engagement, initative bonus, reserves (per day), and surge value will all be based off of the following class dice expressions, each with their own entry (rather than coupled together):

• 1d4
• 1d6
• 1d8
• 2d4
• 1d10
• 1d12
• 2d6

Obviously, when used as an initative bonus, these dice will be part of a roll, but for the other statistics, they will just straightforwardly use the maximum value of the expression. This means that you can still make a subclass like the Wizard have 8 reserves and a surge value of 4, it's just that you'd use 2d4 as their reserve value and 1d4 as their surge value -- rather than saying 1d4 translates to 8 and 4, respectively. 

I can also confidently say that with the little bit of number crunching I've done over the years on the topic, the 1d4 expression will not be used for "reserves per day" -- effectively raising the 'floor' on that number to 6. In the paradigm of most classes having two class dice, the reality is that almost all classes/subclasses will have between 8 and 12 reserves, with the Rogue (Scoundrel) being the obvious exception to this -- although this could just as easily be handwaved to 2d6, if no other subclasses are going to use 6 reserves as their minimum.

Updating Designs

As I've talked about before, this sort of lends to the idea that classes with "1d10" reserves should have a 1/day reserve-burning class feature, whereas classes with "1d12" or "2d6" reserves could have something that's closer to 1/encounter. This actually leans more into the Essentials-style ethos that TNP tries to go for, where some classes have encounter powers and others have daily powers (compared to core 4e D&D, where all classes have both.)

Previously, reserves always had to be rolled in order to regain HP. In recent drafts, this has been revised to only occur during combat, or if your character is at 0 HP once combat is over. Otherwise, spending one reserve will heal you up to full, without needing to roll. This means that the "HP per reserve" is a lot more even across the classes (vis-a-vis surge value) so we can worry less about that as a consideration, in the overall reserve-burning design space.

Looking back at the text of the 2018 playtest version, there were also a couple of other rules that have since fallen by the wayside; classes with a surge value of 4 were given expertise (mastery) on the d20 roll to restore HP, and you gained advantage on the roll if you weren't bloodied yet. This has me wondering if some take on these mechanics could/should make its way into the current rules. Generally, I'm leaning in the direction of having fewer rules and fewer exceptions overall, and just streamlining things where I can.

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As was mentioned in the Discord, I've recently begun work on compiling a new draft of the rules -- which is what led to the topics being discussed in today's post. I'm going to continue to work on this draft, as time allows.

Next post should be up on March 23rd, so check back then for more!

Overview: Class Dice Bonuses (2024)

Recently, I've been giving some thought to how the class dice bonuses work (particularly since finalizing the d12 bonus, in this post which covers the overall topic in great depth.) One thing I was considering is whether "attack and damage" should be the exception or the rule; it turns out those mechanics are kind of split 50/50... At any rate, I figured a big recap of the specific, individual mechanics was warranted. I also want to use this post to try and narrow down what is the most concise way to word the mechanics for each die.

There are a couple of things I should mention first. Since TNP does not use static modifiers (for example, a +3 STR mod or a +2 proficiency bonus, to your attack roll) a total roll of 20 or higher is considered to be a critical hit. This means you can score a crit on a natural 20 on the d20, or by adding to a hit (a d20 roll of 10-19.) Some people are immediately confused by the prospect of some dice bonuses being allowed to be "added to a hit" but this is the reason for that. Similarly, you can add to a miss to improve it to a hit (10-19), which is a bit more intuitive.

As mentioned in the previous post, all class dice bonuses that are not used as the attack bonus are used as a damage bonus. I'm not sure that I've been entirely clear on this point before, so I think it's worth stating here; basically, if there is an exception to this rule, it's that some specific dice can be used as the attack bonus AND as a damage bonus. You can always roll all of the dice bonuses that apply to the attack being made, but you must choose only one of those dice results to be applied as the attack bonus. (Similarly to save bonuses or skills ranks, where you may be able to roll more than one d6, but only apply the highest.) With that out of the way, let's go over each die.

The d4 bonus can be added to either a hit or a miss, and can be used as a damage bonus even if it is used for the attack bonus (i.e. "attack [hit or miss] and damage.") So for example, if the d20 result is a 9, adding a d4 roll (i.e. minimum 1) to it, will turn that miss into a hit; likewise, if the d20 result is a 16, a d4 result of 4 could be used to turn that hit into a critical hit. The special perk for the d4 is that it is treated as having mastery applied to it, but only when used as a damage bonus. This means that if the d4 turns up a 1, it is effectively treated as a +1 to the attack roll, but as a +4 to damage (mastery allows you to treat a 1 as whatever the highest number is, on the die to which mastery is being applied.) So, the d4 bonus provides a small boost to both hit chance and crit chance, as well as a small (but very reliable) damage boost.

The d6 functions similarly to the d4, with the exception that it cannot be used as a damage bonus if it is used as the attack bonus on a roll that would already hit (i.e. if the d6 is used to improve a hit into a crit.) So for example, if the d20 result is a 9, you can use the d6 as the attack bonus and as a damage bonus; if the d20 roll is a 16, you can use the d6 as the attack bonus OR as a damage bonus -- not both. The shorthand I tend to use to think of this is "miss and damage; hit or damage."

The d8 is more straightforwardly "miss or damage." On a hit, the d8 can only be used as a damage bonus; on a miss, the d8 can be added to the d20 result to possibly improve it to a hit. The special perk for the d8 is that if the d8 result and the d20 result are a tie (i.e. the d20 rolls a miss, on the numbers 1 through 8), you can treat the attack as a critical hit; since this perk is considered to be the attack bonus, you cannot use the d8 for a damage bonus if you do so -- the d8 can never be used for both attack and damage. I've always thought of the d8 bonus as sort of "raising the floor" in terms of hit chance.

The d10 bonus in this paradigm is "hit or damage" -- it can either be used to improve a hit into a crit, or it must be used as a damage bonus, only. Since this was found to be just slightly low in terms of the average damage boost, the d10 was given the special perk that (as the attack bonus) the d10 result can be used in place of the d20 result. What this means is that a roll of 10 on the d10 can be used to turn a miss into a hit; essentially, this is a flat 10% chance to improve a miss into a hit. Broadly speaking, though, the function of the d10 is to improve crit chance while offering a large boost to damage.

The d12 is essentially "hit and damage." As was mentioned in the previous post (linked above) the d12 has been given a special attack bonus function, whereby it improves all extra damage dice by treating them as having rolled their maximum result. (For this reason, if this attack bonus is used, the extra damage dice should not be rolled, to prevent mixing them up with the base damage dice, and potentially applying this bonus incorrectly.) Now, the d12 bonus is allowed to be used as damage in addition to providing this benefit, but since this special benefit counts as the attack bonus no other dice may be used as the attack bonus, when and if this benefit is applied. To wit, this means that the attack has to hit on its own merit, or the special benefit couldn't be applied to the extra damage. As an additional benefit, whenever the d12 is used as a damage bonus and the attack is a critical hit, the d12 is treated as having rolled its maximum result; this means that it pairs well with bonuses that potentially increase crit chance.

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Now, the reason that these attack bonuses exist, is because I felt that TNP really needed its own "unique sales proposition" to really set it apart from other systems -- compared to previous iterations, where TNP leaned heavily into the 'advantage' mechanic. I like that by structuring things this way, the attack bonuses are never wasted, on a a hit -- since they can then be translated into damage instead.

It's worth mentioning here, that all class dice bonuses are rolled at the same time as the attack roll. This allows the players to see the potential results of applying one attack bonus vs. another, without the mess having to choose which bonus you're aiming for, and then hoping to roll it. This has the effect of speeding up gameplay; basically, if you miss, you're looking for the smallest bonus that turns it into a hit, and if you hit, you're likewise trying to see if you can turn it into a crit. There really isn't any gambling involved, but the randomness of the dice will present different options depending on the outcomes.

Another interesting quirk of the system is how I've chosen to impliment "combat mastery." Since in 4e D&D, combat advantage was a straight +2 to hit, I wanted something that mimicked this kind of bonus. Simply applying mastery to the d20 would mathematically translate to about a +1 to hit... but it only actually did anything if you rolled a 1. This seemed a little underwhelming, to say the least. As such, combat mastery was expanded to include the attack bonus die; in most cases, this works out to roughly an additional +1 to hit. Doing this means that, for example, a 1 on the d10 bonus can be used to turn a miss into a hit (increasing that 10% miss improvement chance to 20%) while also increasing the ability of the other dice to improve misses into hits (d4, d6, d8), or hits into crits (d4, d6, d10.)

In light of this, since the d12 doesn't gain a benefit from combat mastery (since the number on the d12 result can't be used to manipulate the total of the attack roll) it might make sense as an additional benefit to have combat mastery apply to the d12 bonus as a damage roll... hopefully that wouldn't be too confusing to keep track of.