AC - should it have a cap?

[stoutstien]

Been picking away at my WIP and I came across a note I had in the margin regarding the possibility of having a hard cap with AC that is based on a combination of class, race, and equipment. Has anyone seen something like this implemented?

[Anymage]

Just to clarify. Are you saying that there shouldn't be a point to stacking buffs past a certain point, or that you want an overall AC cap to limit just how wide a difference in ACs you can see among party members? 3e had different buff categories and different bonuses within the same category not stacking, while 5e (at least in theory) was very deliberate to not have wide gaps where one character could not have unhittable or always-hittable AC compared to the rest of the party.

[Vahnavoi]

Depends on whether you want your system to scale indefinitely or not. If you have some kind of auto-hit/auto-miss rule (such as "roll of 20 always hits" / "roll of 1 always misses"), accuracy is already bounded capped that way, you don't need a second cap.

Most systems have some sort of "soft cap" in the sense that at some point a player just runs out of modifiers they can plausibly stack. d20 is a special baby in that it has a ridiculous amount of content, and consequently ridiculous amount of modifiers to stack if a player is allowed to cherrypick. Before worrying about a hard cap, I'd first take a good long look at & consider cutting the amount of character options I'm allowing.

[Xervous]

Explicitly stated hard caps? Yes I’ve seen them, and the usual response is players interpreting it as an expected value. Games that have more defenses that can be targeted don’t suffer from this quite so much. Mutants and Masterminds has explicit expected values all over the place, but the function there is a sliding bar for splitting stats between things so you’re either picking a balanced or lopsided character.

[Khedrac]

Well AD&D explicitly had a cap, originally at -10 (AC got better as it went down), but 2nd Ed allowed dragons to get down to about -13 (it depended on the dragon).
So, yes, I have absolutely seen a cap on AC, but not one that was race/class based.
(Equipment-based caps are common - effectively 3.X D&D does this with the cap of +5 for pre-epic enhancement and dex modifier caps based on armor type.)

Also SciFi games are potentially more likely to have the equivalent of caps - take Traveller - different armors protected differently - but there was no way to modify the protection (at least not in original Traveller) which is equivalent to a cap for that type. Not class or level based as no classes or levels.

[Kurald Galain]

Been picking away at my WIP and I came across a note I had in the margin regarding the possibility of having a hard cap with AC

When playing 3E or PF, I definitely find that the game is less fun if players optimize their AC to the point of being practically unhittable. It's like playing a video game in god mode, really.

[InvisibleBison]

An explicit hard cap (ie, once you have an AC of X further boosts to AC don't do anything) seems like it could be quite frustrating, especially if it's easy to get significantly more AC boosts than needed to hit the cap, people at the cap still get hit a lot, or both. It seems better to me to just build the system so that ACs higher than the desired level simply can't arise.

[stoutstien]

Explicitly stated hard caps? Yes I’ve seen them, and the usual response is players interpreting it as an expected value. Games that have more defenses that can be targeted don’t suffer from this quite so much. Mutants and Masterminds has explicit expected values all over the place, but the function there is a sliding bar for splitting stats between things so you’re either picking a balanced or lopsided character.

I not all that worried about players seeing the cap and expected it to be value to achieve due to the overall cost of everything being compounding rather than linear. Each investment into the same thing cost more and more so you can hyperfocus but it has obvious investment costs.

A brief overview is:
Classes have armor prof which sets the highest bulk they can wear without penalties. Some classes just can't wear armor without it interfering with their abilities without investment. I.e the armored cleric stand in option is giving something up to have that level of protection.

Each class also has a bonus that effect AC. This would be the hard cap in question as it sets the maximum possibly AC regardless of what stuff you strap on or other means of trying to avoid attacks. There are other forms of mitigation available but troupes drive the caps.

Most melee weapons will deal minimal damage even on a miss unless your AC beat it's passive glancing value. Weapons that are good at finding weak points like rodel daggers and big heavy blunt weapons tend to be exceptionally good at bypassing AC this way. Shields and some classes can ignore a certain amount of this damage per scene. Basically it's gear based THP that recharge when you can readjust your gear and catch your breath. **Some actions can prevent this as well. The full defensive mode and get behind me and I'll protect you are alive and well.**

AC from gear alone stays relatively low but higher quality manufactured armor can be flat out immune to attacks not made with heavy 2 hand weapon unless they are also somehow restrained. A trained enemy in plate is a proverbial tank in this regard.

[stoutstien]

An explicit hard cap (ie, once you have an AC of X further boosts to AC don't do anything) seems like it could be quite frustrating, especially if it's easy to get significantly more AC boosts than needed to hit the cap, people at the cap still get hit a lot, or both. It seems better to me to just build the system so that ACs higher than the desired level simply can't arise.

In a perfect world sure but mistakes will happen and Im doing my darnest to avoid content dilving to find the best combos so a well established cap is a safety net.

[False God]

I think a "soft cap" is better than a hard cap, limiting the sources from which you can draw your total AC contributions and then in turn limiting the overall power of those sources. You'll end up with a "maximum AC" if someone was somehow able to get the maximum contribution from each of those sources, but more than likely some of these things would be exclusive and so while in theory you could have 40AC, the best you can actually do is 33, or something.

I don't like hard caps because you can end up wasting resources because you hit the ceiling, especially if there is a variable element to the resource. IE: Defense Spell gives you +1d6 AC, and you roll a 6, but you can only gain 3 more points to hit the cap, so some portion of the spell goes to waste.

---
Alternatively, hard caps pair well with some other mechanics, like threat generation. Back in the before times in early Wrath, late Burning Crusade in WoW, there was a way to get a bear tank to 100% avoidance. That was great for the tank and the healer and certain mechanics, but the problem was it basically dumped their ability to generate threat since at the time, tanks didn't put out much damage. So it was a neat balancing effect in that yes, you could become totally unhittable, but the enemies basically "realized" this via threat generation and started to ignore you in favor of the DPS or healers. And back then, getting aggro back was HARD, taunts were only temporary increases in aggro and most aggro was based off actual actions taken and damage done to the enemy.

So, caps can be useful when paired with other mechanics. D&D doesn't really pair AC with another other mechanics that encourage you to balance it out, it's more of a "max out all the numbers" sort of game, with the more maxed out numbers you have, the better you'll perform. There's no consideration of "Well, if I max this out, other aspects will suffer." Those considerations naturally make a game more complex, which creates a barrier for entry, but gives people more choice points.

[gbaji]

The question is massively dependent on how AC is managed by the game. But most games will tend to have some scaling values that represent "how well opponents can dish out damage" versus "how well you can take damage".

D&D basically does have hard caps in that you can only wear one set of armor (with limits on AC), and AC bonuses due to magic are limited (+5), and <whatever> of protection items are limited as well (also +5). And then there are various buffs that may increase by some amount as well (some which stack, and some which don't). The assumption is that as to-hit values increase (with level/HD), this will balance against better gear/spells available, leaving everything nicely inside a D20 sized "window" that scales up with level.

Where things get dicey (which I think someone mentioned previously) is that there are additional odd abilities/feats/whatever that designers introduce into the game that add more "stuff". When these are in play, it can cause problems with the assumed balance of to-hit vs AC. As a GM, you can actively disalow these things, if that's what you want to do. You should feel no pressure at all to include "everything ever published anywhere for this game system" in your own game. I think this is a better solution than allowing these things, but then saying "Yeah, but you don't get to take advantage of these special abilities because I'm capping your values anyway".

As a GM, it's usually a bad idea to appear to give something to the players, but then take it away after the fact. Player expect that their abilities will have an effect, so if they reach a point where they don't, it's a problem. Since (for D&D anyway) to hit effects are already capped via nat20/1 roll results, the only way including an additional cap would have an effect would be to stop that prior to reaching those edges of the "window', and I'm not sure that's a great thing to do.

Dunno. I'd just let the D20 window "work" here and move on. That already creates a case where adding more AC past a point doesn't help you against some opponents. Which, to be fair, is exactly what should happen.

I think a bigger issue is in-party balance. This can be particularly problematic in game systems where level/class causes gradually/steadily increasing "gaps" between AC focused characters and non-AC focused characters. This can reach a point where the same set of NPCs can only hit one character on a nat20, while only missing another character on a nat1. How much of a problem this is depends on the party makeup and how often the wimpy dress wearers are being attacked directly. To me, this maybe isn't a problem. It's often the tradeoff between different types of characters, right? One can argue that it would be unfair for the character who choose a defensive build to be effectively penalized for this, while the character focused on offensive damage isn't.

So... um... It depends?

[Maat Mons]

With regard to making AC / max AC class-based, how does that interact with multiclassing? Do you basically wind up wearing armor corresponding to the lightest-armored class in the mix? Or do you basically wind up wearing armor corresponding to the heaviest-armored class in the mix?

So, you fiddle with some things (class, race, equipment, you said) to raise your AC cap. And then you fiddle with some things (no idea what) to raise your AC to the cap. I’m not really seeing the benefit of making the fiddling a two-step process. A one-step process could just as easily be designed to ensure all the same design goals are met.

As a wacky alternative, maybe which numbers on the die auto-hit and auto-miss isn’t a universal constant, but instead can be influenced by the abilities of the target. So, if your system is based on rolling 3d6, an attack against an average enemy could auto-hit on a 15+ (10% chance), but a tankier characters might require 16+ (5% chance), 17+ (2% chance) or even 18 (0.5% chance) to auto-hit them.

[stoutstien]

With regard to making AC / max AC class-based, how does that interact with multiclassing? Do you basically wind up wearing armor corresponding to the lightest-armored class in the mix? Or do you basically wind up wearing armor corresponding to the heaviest-armored class in the mix?

So, you fiddle with some things (class, race, equipment, you said) to raise your AC cap. And then you fiddle with some things (no idea what) to raise your AC to the cap. I’m not really seeing the benefit of making the fiddling a two-step process. A one-step process could just as easily be designed to ensure all the same design goals are met.

As a wacky alternative, maybe which numbers on the die auto-hit and auto-miss isn’t a universal constant, but instead can be influenced by the abilities of the target. So, if your system is based on rolling 3d6, an attack against an average enemy could auto-hit on a 15+ (10% chance), but a tankier characters might require 16+ (5% chance), 17+ (2% chance) or even 18 (0.5% chance) to auto-hit them.

My system doesn't have lv by lv multiclassing so that's a big headache I don't need to deal with.

The reason why I broke it up was that I wanted to add a lot more nuance to mitigation without a ton of overhead. AC isn't just a thing you get the most you can grab at the lowest cost and dall it good because it's a constant trade off. Some classes just have a head start and an overall higher threshold.

For example the <rogue> can wear a decently wide range of armor depending on ability score investment but the heavier the armor gets the less often they can dodge attacks that would hit them where the <barbarian> can absorb a large amount of damage but have few ways to avoid it completely unless they slap on heavy armor but that reduces the amount they will be able to soak due the increased energy needed moving around in equipment and they kinda want to be hit to build rage.

[gatorized]

Prowlers uses a single trait cap for every power, ability, and talent. Works well.

[Anonymouswizard]

It might be wortyh looking at 13th Age for this, AC is effectively based on class as it determines what level of AC and penalties each category gives (so you'll generally want the highest you can get without penalkties). The game also theoretically does this for weapon damage, but out of all the classes I have access to only two stray from default damage values (the Rogue and Monk).

Note that it's not quite as simple as 'warrior classes get better armour', the Fighter is better in light armour than the Paladin but worse in heavy armour. But in general you're going to be wearing the best armour you can, and so it pretty much comes down to AC being based on class with slightly more nuance than the D&D implementation.

Although honestly at the end of the day simpler is probably better, which is probably why most games don't bother with glancing blows or certain weapons being better at penetrating certain armours. If AC is already practically capped and you're not planning to add a ton of new abilities to the game (i.e.e this is more of a Fantasy AGE than a D&D) then having an explicit hard cap might just not be worth it.

[stoutstien]

Although honestly at the end of the day simpler is probably better, which is probably why most games don't bother with glancing blows or certain weapons being better at penetrating certain armours. If AC is already practically capped and you're not planning to add a ton of new abilities to the game (i.e.e this is more of a Fantasy AGE than a D&D) then having an explicit hard cap might just not be worth it.

The ultimate goal would to set it up so there would be nearly infinite options for creating new player options as needed. The base classes would be fixed but will have 2 "subclass" options that have guidelines for adding content as needed/wanted. It's embedded into the character creation process which is heavily travelers inspired where it's not something you just waive off before you start playing.

The cap in question would be more of a warning sign for tables when developing characters that it's starting to push the edges of what the system will support without a more active hand in the core math and you start running the risk of reducing options by addition.

[NichG]

If you're going to make a system with a lot of content, I strongly agree with designing some rules as 'ends' (this value should never be above 25) rather than 'means' (I will make all my rules keeping in mind all my other rules at all times, so that the value cannot be above 25).

But you could also design this into the way AC functions by using math that bakes in diminishing returns. With a linear roll vs value system, the closer you get to exceeding the variance, the more valuable each extra point becomes - going from being hit 10% of the time to being hit 5% of the time halves your damage taken.

Instead you could have AC work like, if your AC equals or exceeds the enemy's weapon penetration (not attack bonus, purely a property of the nature of the attack) then you gain a flat 75% (50%? maybe make it 50% for meet/exceed, 75% for doubles?) miss chance; similarly, when attacking you only have to roll your attack skill against a fixed DC of 15 modulo circumstances or things like target size or distance for ranged. So an attack bonus of +100 just doesn't do anything. Crits can bypass AC and bludgeoning weapons can have lower pen values but only a 25% miss chance from armor rather than 50% or 75%.

This will give a game with a much more compressed power range than, say, D&D.

Or another example would be AC as a dice pool where each point of AC lets you roll a d6, and if you get at least one 6 then you take half damage from the attack.

[Xervous]

I not all that worried about players seeing the cap and expected it to be value to achieve due to the overall cost of everything being compounding rather than linear. Each investment into the same thing cost more and more so you can hyperfocus but it has obvious investment costs.


So you’ve got increasing investment cost. How easy is it for a creature to target a different defense? The difference between 40 or 101 AC is meaningless if there’s an easier avenue for attack.

[stoutstien]

So you’ve got increasing investment cost. How easy is it for a creature to target a different defense? The difference between 40 or 101 AC is meaningless if there’s an easier avenue for attack.

That's a tough question to answer without just posting the whole system and it's rat nest ATM because i work well in chaos.

The different approaches do exist but they aren't easy and will bring in the question of the morale, tactical level, and overall intelligence of an enemy force.

Most bandit gangs would probably let the knight in full plate go by without harassment unless they are really desperate or they had a trap in place for such occasion as being restrained would take away a lot of that particular armor's features.

I don't think I see a way for anyway they can be bypasses without plenty of times the party to shift away from that issue. Besides getting just mobbed down and even then they probably walked past a dozen warning signs to get there.


Basically if they invest in it they will be good at it but having a little diversity in the tool box will probably go further than stacking after a point.

[MoiMagnus]

If your players are good with maths, you can include regressive bonuses.

One simple example is "when you get bonuses to AC, you select one bonus that count at 100% but the others are only worth 50%"

One more complex example is "average with". In a practical situation, instead of giving +5 to AC, the shield spell would be giving "your new AC is the average of your old AC with 22 AC, rounded up".

[stoutstien]

If your players are good with maths, you can include regressive bonuses.

One simple example is "when you get bonuses to AC, you select one bonus that count at 100% but the others are only worth 50%"

One more complex example is "average with". In a practical situation, instead of giving +5 to AC, the shield spell would be giving "your new AC is the average of your old AC with 22 AC, rounded up".

Mostly that is built into the pro/con of the armor.

So there are 3 plate options:

Fitted Plate - moderate AC (~50% avoidance) but immune to one handed weapon attacks, light quarrels, and <quick> natural weapon attacks unless you are restrained or the enemy uses coordinated attacks.
Bulk: low
Cost: high. *Each suit is made for one person.*
Don/doff speed: slow/fast with assistance.
Weakness: heavy weapon attacks and being overran.

Field plate - moderate AC(~60% avoidance )with soak value (THP that comeback after you catch your breath and/or adjust gear. As long as you aren't having back to back fights it's something you'll have)
Bulk: moderate
Cost :low
Don/doff speed : fast
Weakness: draw out combat

Living fortress plate- highest AC available (~80-90% avoidance) immunity to certain effects due to sheer mass. Built-in weapons.
Bulk: very high. Limits movement speed/ certain mobility options
Cost: moderate
Don speed: slow
Doff speed: fast
Weakness: speed and weapons that have high glancing values (minimal damage even on misses if they can beat the AC)

[Maat Mons]

I’m by no means an expert, but I thought the types of plate were:

Cuirass: Torso fully covered.
Half Armor: Torso fully covered. Front of thighs and outside of upper arms covered.
Three-Quarters Armor: Torso fully covered. Front of thighs covered. Full length of arms covered, but only outside part of arms on cheaper versions.
Full Armor: Torso fully covered. Full length of legs covered, but only front part of legs on cheaper versions. Full length of arms covered, but only outside part of arms on cheaper versions.



Also, you mention the weakness of one of the types of armor being “drawn out combat.” Wouldn’t that be a weakness shared by all weighty armors? Especially ones where much of the weight is on the arms and legs? I thought that was the main reason, other than cost, people didn’t all opt for the heaviest armor available. You’ve got to keep weight down, so you don’t tire out as the battle drags on.

Do you have a stamina system? Wearing armor could increase the stamina cost of various actions. The magnitude of the increase could be greater for heavier armors. This would provide an incentive for wearing lighter armors, beyond just proficiency considerations.

I think the three main cases for getting attacked while wearing armor are:
The attack misses you. You take no damage.
The attack hits you, but somewhere the armor covers. You take damage, but the armor provides its damage reduction.
The attack hits you somewhere the armor doesn’t cover. Take full damage.

It feels like your “glancing blow damage” idea is meant to approximate this, but I don’t think it makes sense for it to be a property of the weapon. Glancing should instead be a property of the armor. After all, if you’re not wearing armor, there’s nothing for a weapon to glance off of. An unarmored person should really just either take full damage or no damage, depending on if they dodge. The easiest way to model it would be to give everyone two different ACs. A lower one to negate attack that roll lower. And a higher one to suffer a lesser effect from attacks that roll lower. Well, except for unarmored people. They’d have just the one AC. Or both ACs would be the same. However you want to look at it.

For representing that some weapons are heavier, you could give big weapons “penetration,” or some such. A value by which any damage mitigation the target has is reduced. Oh, and if you have a stamina system, attacks with heavier weapons cost more stamina, obviously. You might also get fewer attacks per round.

This would all be very complicated, but I get the impression you like complicated.

[stoutstien]

I’m by no means an expert, but I thought the types of plate were:

Cuirass: Torso fully covered.
Half Armor: Torso fully covered. Front of thighs and outside of upper arms covered.
Three-Quarters Armor: Torso fully covered. Front of thighs covered. Full length of arms covered, but only outside part of arms on cheaper versions.
Full Armor: Torso fully covered. Full length of legs covered, but only front part of legs on cheaper versions. Full length of arms covered, but only outside part of arms on cheaper versions.



Also, you mention the weakness of one of the types of armor being “drawn out combat.” Wouldn’t that be a weakness shared by all weighty armors? Especially ones where much of the weight is on the arms and legs? I thought that was the main reason, other than cost, people didn’t all opt for the heaviest armor available. You’ve got to keep weight down, so you don’t tire out as the battle drags on.

Do you have a stamina system? Wearing armor could increase the stamina cost of various actions. The magnitude of the increase could be greater for heavier armors. This would provide an incentive for wearing lighter armors, beyond just proficiency considerations.

I think the three main cases for getting attacked while wearing armor are:
The attack misses you. You take no damage.
The attack hits you, but somewhere the armor covers. You take damage, but the armor provides its damage reduction.
The attack hits you somewhere the armor doesn’t cover. Take full damage.

It feels like your “glancing blow damage” idea is meant to approximate this, but I don’t think it makes sense for it to be a property of the weapon. Glancing should instead be a property of the armor. After all, if you’re not wearing armor, there’s nothing for a weapon to glance off of. An unarmored person should really just either take full damage or no damage, depending on if they dodge. The easiest way to model it would be to give everyone two different ACs. A lower one to negate attack that roll lower. And a higher one to suffer a lesser effect from attacks that roll lower. Well, except for unarmored people. They’d have just the one AC. Or both ACs would be the same. However you want to look at it.

For representing that some weapons are heavier, you could give big weapons “penetration,” or some such. A value by which any damage mitigation the target has is reduced. Oh, and if you have a stamina system, attacks with heavier weapons cost more stamina, obviously. You might also get fewer attacks per round.

This would all be very complicated, but I get the impression you like complicated.


This isn't so much about realism as providing tools for conceptual fulfillment. though when talking about plate armor it was much lighter than people realize and weight distribution is more important than the scale weight (that's what bulk is for b/c tracking weight is silly in ttrpgs). No one is actually going to wear a set of jousting plate in combat IRL but being a hulking pile of armor is a common fantasy trope.

The reason why one plate is weaker in drawn out combat is it just has less coverage overall so as the fight goes on the odds of a blow connecting on an unprotected area increases. This is your breast plate and helmet or other forms of plate that require the user to be conscious of the areas lacking protection. The THP pool might get changed to a more simple approach like you can just ignore X amount of successful attacks(including glance) instead.
That and it's just a different option depending on how much they want to rely on luck vs preparing.

Glancing is mostly a place holder name for:

-damaging that will occur in melee combat regardless of how much protection you have.

-The minimum damage one would do against a target you can reasonably hit with that weapon.

So say a mace would have a rating of 2/16 AC. As long as the target has 16 AC or lower every attack will deal some damage. As a general rule slashing deals high glance but it has a lower AC threshold, blunt has low damage but high AC threshold and piercing weapons have low damage but a high AC threshold. It has a pretty basic formula so player/DMs can create a huge range of weapons with a single dial.

[mig el pig]

When playing 3E or PF, I definitely find that the game is less fun if players optimize their AC to the point of being practically unhittable. It's like playing a video game in god mode, really.

Yep, and at that point it's likely to turn into an arms race with the DM, leaving all the players who didn't participate in the dust.

I don't really see a way out except making a difference between hard to hit and hard to damage like some other RPG's but then you're homebrewing one of the corner stones of DnD which would have so many repercutions you're basicly starting from scratch.

[stoutstien]

Yep, and at that point it's likely to turn into an arms race with the DM, leaving all the players who didn't participate in the dust.

I don't really see a way out except making a difference between hard to hit and hard to damage like some other RPG's but then you're homebrewing one of the corner stones of DnD which would have so many repercutions you're basicly starting from scratch.

My WIP is more OSR/oddball in nature anyways so the only thing it really shares with DnD is my conversion tables for stat blocks. Shares some fantasy support and terminology just because there is only so many ways you can call for a saving throws.

I pretty much went full demon barber on fleet Street on sacred cows.

[Xervous]

That's a tough question to answer without just posting the whole system and it's rat nest ATM because i work well in chaos.

The different approaches do exist but they aren't easy and will bring in the question of the morale, tactical level, and overall intelligence of an enemy force.


My question is more “so he has high AC, but what about his save vs. rods?” Does the game mainly use just AC or are there other resists that can be targeted?

[stoutstien]

My question is more “so he has high AC, but what about his save vs. rods?” Does the game mainly use just AC or are there other resists that can be targeted?

AC covers a lot but there are other types of saves but it's under a "pick your best from 2 ability scores" system so you are good at things you'd assume you would be good at. For example you could use grit or nimbleness to deal with a fireball type effect. Also everyone is basically proficient in saves so even if they don't invest they will get better at them to some degree so they never have a "never pass" situation.

[gbaji]

I don't really see a way out except making a difference between hard to hit and hard to damage like some other RPG's but then you're homebrewing one of the corner stones of DnD which would have so many repercutions you're basicly starting from scratch.

Like a lot of things, including how HPs are managed (probably?), and weapon damage (almost certainly) as well. I play regularly in a RQ game, and in that system, damage taken in combat just works differently (and not just in the ways you'd expect). It has some odd resource effects, that are also quite different. I can literally run the same exact character, with the same exact gear in two fights, against similar foes, and in one I'll exit the battle without taking a single point of damage, and in the other I've been smacked around and had to use serveral heal spells. In games with segregated "hit" and "damaged" defense elements, the difference between "took no damage" and "I'm lying on the ground in a pool of my own blood" can be very very small (or just subject to random luck). D&D? You can more or less calculate an average rate of damage per round based on your AC and your opponents to-hit values, compare to your HP total, and figure out resources spent over time while fighting. There are some nice aspects to that, but there is absolutely a resource maagement component as well.

So yeah. It's not as simple as just spackling a different AC/to-hit formula in there.

I'll also point out that game systems, somewhat by design, require some sort of "decision balance". I reality, some choices are always going to be better than others though. You need to be careful about artificially creating "balance points" where maybe they may not need to be. This becomes even more problematic in most RPGs because we can only simulate so much. So things that might be a balance point in real life (cost, availability, ease to maintain, and even weight) may not be tracked at all in the game. This leads us to create new balance points for these things, even if they may not make any sense realistically.

We see this with armor a lot of time, trying to "balance" heavy and light armors. We also see this with weapons as well. But if your game system doesn't track the aspects of these things that would normally be a blance point, you kinda don't have much choice. The alternative is "everyone uses this cause it's always best", which is not great from a gameplay perspective.

So yeah. You have to decide the level of realism you really care about, versus just making a playable and enjoyable game system.

[Pauly]

My view is that AC should only be capped if to hit is also capped.

Whether AC and THAC0 should be capped is another question. Simple answer is it depends on how easily/often players can reach the limits in play and the range spread of the dice vis a vis the range spread of dice modifiers.

If you're hitting the limit in half the combats then the cap should be removed. If the modifiers are bigger than the dice you're using then a cap should be applied.

[Xervous]

AC covers a lot but there are other types of saves but it's under a "pick your best from 2 ability scores" system so you are good at things you'd assume you would be good at. For example you could use grit or nimbleness to deal with a fireball type effect. Also everyone is basically proficient in saves so even if they don't invest they will get better at them to some degree so they never have a "never pass" situation.

If my monster attacks for 20 damage at a +10 against AC, or can throw a firebolt for 10/+10 against a save, there’s a point past which a player boosting AC won’t affect their own survivability because the monster does more by throwing firebolts. In such a system where investment is granular, one of the main reasons to cap something like AC is to keep players from over specializing at the expense of other defenses.

[stoutstien]

If my monster attacks for 20 damage at a +10 against AC, or can throw a firebolt for 10/+10 against a save, there’s a point past which a player boosting AC won’t affect their own survivability because the monster does more by throwing firebolts. In such a system where investment is granular, one of the main reasons to cap something like AC is to keep players from over specializing at the expense of other defenses.

There is definitely a big push to diversity over being hyper specialized though the NPCs do have a layer of mechanics to keep them from doing the best action based on the math.

Survivability will be more of an action and active decision focus rather than a passive stat to build up. Sure the mighty holy warrior can stand against the horde of undead. Just not indefinitely so they need to adjust to the flow changes.