Guaranteed Damage Reduction Documentation

[edgefigaro]

Hi, I'm edge. I have 2 wins, a few hundred games played, read this forum regularly, and have heard GDR (always as GDR) mentioned often but never knew exactly what it was. In the major background trimming thread Cragspyder said the following, and it somewhat resonated with me.

(use of all caps has been removed )

Did you know that a +1 robe is not flat out better then +0 leather armour? Find that out through the game? You can't. I was randomly flicking through the Crawlwiki article on armour when I found out, by accident, about Guaranteed Damage Reduction. If you click on a piece of body armour in game, it makes no mention of this. The only hint to this feature is in the items section of the manual:

"On the other hand, body armour will have some guaranteed reduction against melee attacks, and heavier armours are better at this."

One line of one massive text file, and even then there is no information in game to say for sure how much GDR leather armour provides compared to a robe.

GDR could use some better documentation, as it is significant when comparing armors. Part of the fun of crawl is making informed choices about gear and the relevant trade offs, it should be easier than it is now to be informed about this aspect of armor.

[Sar]

it is significant when comparing armors

It actually isn't!

[edgefigaro]

it is significant when comparing armors

It actually isn't!

I'm sorry, I don't know what you mean. When i compare a +x leather to a +y ring mail, i attempt to intuit (in no particular order) (1) If the defenses are similar, (2) competing brands, (3), impact on spellcasting, armed and unarmed melee attacks. stealth. Alot of times these are very subtle differences. Then I make a judgement call, and decide which I want to use.

I've played the game a bit and have a I like to think I have a decent intuition about how changing armor types affects spellcasting, melee attacks, stealth. It should be just as easy to know about the GDR aspect of armor.

That isn't to say, it needs to be in boldface letters plastered on the screen. I'm just saying the current documentation could use a rehash.

"Heavier armors also reduce the most severe melee damage spikes innately."

I didn't know this, and to some extent I think I should have, having played the game as much as I have.

[crate]

GDR is so closely correlated to your total AC that it doesn't really ever change a decision you would make. If you have equal AC with two different armours (because of different enchantment) it turns out that the lighter (lower GDR) one is typically better anyway (more EV, lower accuracy/spellcasting penalty). All you need to know when making decisions is the AC and EV you end up with.

+0 leather vs +1 robe is pretty much the only exception to this but now that leather actually has spellcasting penalties (though small) that might not even be true there any more either.

---

If you want to argue about whether GDR should exist, that's a different thing, but I really don't think crawl needs to tell you about it. There are much more significant things that crawl hides (spell accuracy and damage is an easy example), as a design decision, so you're not going to get this one.

[Sprucery]

One thing maybe worth mentioning is that if you're used to playing armored characters and have a gut feeling what it's like to fight with, say, 35 AC, you may be surprised if you play for example a draconian and have the same 35 AC and no GDR. I don't know if this is a real issue.

[Sar]

I've heard people saying it's noticeable but I've played a lot of robed Nagas and never really noticed it. Then again, I am not very attentive!

[Pereza0]

Hmm... Maybe GDR could be turned into something intrinsic to AC and that scales with it. They tend to go together anyway, if this is considered a nerf to heavy armour maybe the could get a bit more AC to compensate. AC feels weaker on Draconians with me but I can't tell if it is me actually noticing it or a placebo kind of thing and this would help that

[Sandman25]

I've heard people saying it's noticeable but I've played a lot of robed Nagas and never really noticed it. Then again, I am not very attentive!

Try +0 Troll Leather Armour and +2 robe with Ozocubu's Armour, Chei and Archmagi.

[BrewFall]

One of the design goals of crawl is to obfuscate information to prevent this sort of analysis. You are meant to make decisions through intuition rather than reasoning.

[comebackshane]

From the learndb (https://crawl.develz.org/wiki/doku.php? ... 0.16_plans):

GDR reform — an invisible number. if it's significant, it should be exposed to the player in some way. (“plate armour provides somewhat more protection against melee attacks than a choko”…?) It might be nice to simply associate it directly with AC, or remove it altogether, but there are significant balance considerations involved. this is not going in 0.16, sadly.

It takes the words out of my mouth.

Also, I recently played so many draconians (read: sent them to their demise) that you can use the pile of their corpses as a stairway to reach the summit of Mt. Everest. It looks like a rainbow with all the different scale colors!

Anyway, having played a race with no body armour I quickly realized that having or not having GDR does make a difference. But of course, there were many other reasons why they died, just pointing out that GDR can not be ignored entirely when it comes to defensive stats. You can always suffer high spikes of damage despite having the same AC as an armoured character.

[Sar]

Try +0 Troll Leather Armour and +2 robe with Ozocubu's Armour, Chei and Archmagi.

How would that be different from playing a plate dude with 40 AC (which I did) vs. playing a robe Naga with 40 AC (which I did as well, more than once too)?

[edgefigaro]

One of the design goals of crawl is to obfuscate information to prevent this sort of analysis. You are meant to make decisions through intuition rather than reasoning.

This is what I love about crawl. I like that sense of reasoning. I like to be aware of a mechanic more than I need the numbers. I had no idea that my defenses are different if I had an early ring of robustness on an ogre at D6 as opposed to an ogre that had a +2 steam dragon armor and a +2 cloak. And I want to be able to intuit such things.

Does it matter? I'm prolly still just going to chuck a bunch of tomahawks at things and then zerk if they get close.

[Sandman25]

I had no idea that my defenses are different if I had an early ring of robustness on an ogre at D6 as opposed to an ogre that had a +2 steam dragon armor and a +2 cloak.

They are not different in this case provided you meant +0 robe for the former.
Even in an extreme case of Troll Leather Armour + Ozocubu's Armour you can have something like AC 30. GDR for TLA is 19% so you reduce monster damage by at least min (30/2, monster_max_damage*0.19). For example, if you are attacked by a monster with max damage 6, you are guaranteed to reduce damage by 1. If you are attacked by a monster with max damage 30, you are guaranteed to reduce damage by 5. Low GDR is not that great.

Edit. I forgot GDR is capped by AC/2, not AC*GDR.

[edgefigaro]

I had no idea that my defenses are different if I had an early ring of robustness on an ogre at D6 as opposed to an ogre that had a +2 steam dragon armor and a +2 cloak.

They are not different in this case provided you meant +0 robe for the former.
Even in an extreme case of Troll Leather Armour + Ozocubu's Armour you can have something like AC 30. GDR for TLA is 19% so you reduce monster damage by at least min (30*0.19, monster_max_damage*0.19). For example, if you are attacked by a monster with max damage 6, you are guaranteed to reduce damage by 1. If you are attacked by a monster with max damage 30+ (no matter if it's 30 or 200), you are guaranteed to reduce damage by 5. Low GDR is not that great.

Ring of Robustness, +0 Robe = 9A, 0% gdr // +2 Steam dragon armor, +2 cloak = 9 AC, 24% gdr. In the former there is no GDR, in the latter there is. My defenses are different. It may not be a huge effect, but it is there, and I want to know it is there.

[Sandman25]

Steam dragon armor [skipped] 24% gdr.

Oops. I learned something new today, thanks.

[Pereza0]

Ring of Robustness, +0 Robe = 9A, 0% gdr // +2 Steam dragon armor, +2 cloak = 9 AC, 24% gdr. In the former there is no GDR, in the latter there is. My defenses are different. It may not be a huge effect, but it is there, and I want to know it is there.

Yeah, crawl has always been obtuse about its in-game mechanics.

I think it is something that should be addressed without relying too much on overwhelming the user with numbers, but if you are into that stuff check out ToME4 or Sil, they both do a great job at that.

[duvessa]

ToME4 does a great job of overwhelming the player with numbers but the last time I played it, it was ridiculously obtuse about its in-game mechanics in spite of that. Probably even as much as DCSS is. I had to do a similar amount of source diving, although ToME4's code is slightly better than Crawl's.

Personally I'd like it if GDR were removed (and armour base AC, statue/dragon form buffed a bit) because it's weird in so many ways - inconsistently applied, inconsistently acquired, and makes AC behave in a way that I really would not expect it to. 1d(AC+1)-1 is also a nice, simple rule that would be good to tell players about IMO, but you can't do that until you make it actually true in most cases (you'd also want to change tornado and awaken forest I guess but to me that sounds like a good thing independently).

[Pereza0]

ToME4 does a great job of overwhelming the player with numbers but the last time I played it, it was ridiculously obtuse about its in-game mechanics in spite of that. Probably even as much as DCSS is. I had to do a similar amount of source diving, although ToME4's code is slightly better than Crawl's.

I was referring to Crawl when I talked about not overwhelming with numbers. I would have never said the same about ToME4 (much the opposite) but my phrasing was pretty ambiguous.

I felt the tutorial did a pretty good job explaining what the attack/resist numbers did, but then again I never dived in deep enough to think realize there could be anything unexplained beyond those.

[and into]

GDR only applies to melee damage (not ranged combat damage, not magic damage of any type, not "ability-based" damage from breath attacks, etc.) and it also does not do exactly what it says on the tin. The formula is not as simple as you might think, and, among other things, it is capped by your total AC. So having relatively high GDR with a low AC value makes GDR *even less* significant than it otherwise would be!

Ring of Robustness, +0 Robe = 9A, 0% gdr // +2 Steam dragon armor, +2 cloak = 9 AC, 24% gdr.

It is actually 10 AC in both cases. Also, there is no practical situation in any game where you would be making a decision between these different set ups. (Obviously you would wear the SDA, the enchanted aux armor, and the ring of robustness, unless possibly the robe is archmagi.)

Setting all that aside, this is a good illustration of why knowing/caring/thinking about GDR is actually misleading. You look at that and say, wow, 24% higher GDR; that must mean something, right?

Well...

With 24% GDR (SDA and +2 hat), 10 AC and 12 EV, your incoming AED is
0.6, against a hound
2.7, against a yak
12.4, against a stone giant

With 0% GDR (robe + robustness), 10 AC and 12 EV, your incoming AED is
0.6, against a hound
3.3, against a yak
12.9, against a stone giant

In the latter case, having somewhere between 2 and 3 more AC, while keeping 0 GDR, will yield the same results as the SDA.

So that 24% GDR translates into this: "Against enemies that hit hard enough (no difference with hound), *in melee only*, you get effectively a couple more points of AC."

Keep in mind that it is very rare that you will be choosing between two body armors that offer a difference of 24% GDR while offering the same AC/EV value and no meaningful spell success differences, and again keep in mind the very situational application of GDR in the first place (melee only), and you will begin to understand why the common advice is to pretend GDR doesn't exist: In the overwhelming majority of cases, it isn't actually going to alter your decisions.

So yeah, I'd second duvessa. If anything is going to change here, I'd suggest simplifying matters by giving heavier armors an AC buff (proportional to the amount of GDR they currently offer) and get rid of GDR altogether. That would be a lot better than giving GDR documentation, at least, since that would just be extremely confusing and not-helpful (actively misleading, actually) in the majority of cases.

[johlstei]

Is AED average expected damage? I think it would be most fair to do worst case analysis - at least to me that seemed like the design goal of GDR, to make heavy armour slightly better in the average case but have a significantly better worst case. (Whether this is a good design goal I won't comment on, my only claim is that it reads as the intention there.)

[and into]

Is AED average expected damage? I think it would be most fair to do worst case analysis

Well, that's pretty easy: Stone giant gets its max hit reduced by 5 (10/2), so it does 40 instead of 45 max dam. Yaks... max dam probably reduced by 5? Close to 5. So like 13 or 14, rather than 18. Hounds by much less because their max damage is so low, in that case it isn't going to matter.

GDR helps more by this metric, but that's even more situational; it is not common that a stone giant both hits you and does 45 for damage. And, again, this is already only a subset of the situations in which a stone giant is actually dangerous (GDR does literally nothing if the stone giant throws a large rock at you).

My main point is about why documenting GDR would be a bad idea. If you don't explain what it is, just give them the %, it is very misleading. If you do try to explain it, it is actually at least a little complicated; there is a difference between when your total AC is the "limiting factor" vs. when your GDR is, and which is the limiting factor depends on the potential *max* damage of the melee damage roll, which is information that is not given in game.

Since the average, overall usefulness of GDR is extremely similar to just having somewhat higher AC, I think that removing GDR and increasing AC from armors a bit would be a much better idea than telling players about GDR in-game.

[johlstei]

Yeah I certainly agree with your conclusion regardless, I proposed removing it with no other changes needed it Duvessa's "changes to make crawl harder" thread. Its clear that I still had misconceptions about how it worked anyway.

[tasonir]

The point of GDR is to reduce worst case damage, not average damage. So I completely disagree with and_into's statement "Since the average, overall usefulness of GDR is extremely similar to just having somewhat higher AC". Higher AC can still roll 0, GDR will always take damage off that stone giant who might otherwise hit you for 50 damage. I'm not worried about the average case. The average case is that I win every fight in crawl with a large margin of safety. I have to worry about those 5% of fights where I suddenly take far too much damage and have to resort to emergency measures or else another bad hit will kill me.

It's been ages but yes, back when I did play a draconian transmuter I do remember taking far more damage than I expected from a few hard hitting melee monsters. It's noticeable to me. Of course, I'm also the guy who's crazy enough to actually still use statue form on a draconian after my dragon form draconian died...Yes I know dragon form also has GDR, it was that lack of general defenses that did that character in.

[Siegurt]

Well, we could start by simplifying it and making GDR be simply a factor of armour's ER, so it'd at least not be a weird Dragon armour vs. not-dragon-armour thing.

Distilling the formula into something that one could easily and accurately explain in three to five words would also be a big help.

Finally putting those three to five words in the armour's description would be an excellent addition.

[tasonir]

GDR is a simple factor of an armor's base AC as it stands. Not sure why you'd want to tie it to ER instead. What I was talking about in my post was draconians, who get decent AC with no GDR, not the difference between dragon armors and metal armors, ie plate, chain mail, etc.

[duvessa]

tie GDR to HP

[Siegurt]

GDR is a simple factor of an armor's base AC as it stands. Not sure why you'd want to tie it to ER instead. What I was talking about in my post was draconians, who get decent AC with no GDR, not the difference between dragon armors and metal armors, ie plate, chain mail, etc.

Well, tying it to AC rather than ER means that dragon armour is direct upgrade with no tradeoff for any given amount of penalty, using ER instead would make Dragon armour at least a tradeoff of evasion for GDR.

Not that that's important one way or the other, the more important thing would be to make it something we can describe and that we do so.

[Pereza0]

Well, tying it to AC rather than ER means that dragon armour is direct upgrade with no tradeoff for any given amount of penalty, using ER instead would make Dragon armour at least a tradeoff of evasion for GDR.

Not that that's important one way or the other, the more important thing would be to make it something we can describe and that we do so.

The problem is that as it currently stands in the game there is little way for a player to know it is not a direct upgrade. Might as well make it so. Or...

I think a decent way to go about it would be to tie GDR to AC, then making mundane armours have a little bit more AC than their lighter dragon counterparts.

That way looking at your AC gives you more information about your defenses. And also helps poor draconians (poor guys, while Gargoyles and Tengu are wearing armour and flying all over the place at the same time Draconians get to do neither . Other than black ones of course)

[and into]

GDR is a simple factor

It is not. Well, maybe it is to you, but people constantly misunderstand it, and the way it actually functions in the game.

The OP's point, and the point of the thread, is about (I think) trying to give people all the information they need to make decisions. It is a very unusual case indeed where having the knowledge of GDR and how it works will actually lead you to alter a decision. However, it remains a game mechanic that is prone to being misunderstood, when people do hear about it. So basically the game should either stay as it is now, or else change GDR. Giving the player the GDR value, with no additional information, would be actively misleading. Trying to explain what the GDR value actually means would be drawing even more attention to something that very rarely matters in terms of actual game play decisions. Ergo, GDR should be changed/removed, or else the current (no documentation) status quo, whatever the problems with it, should be retained.

So I completely disagree with and_into's statement "Since the average, overall usefulness of GDR is extremely similar to just having somewhat higher AC".

You are misunderstanding my point. The "average usefulness," that is, the AED reduction, of GDR is extremely similar to just having higher AC. I do not dispute that the usefulness of GDR in "worst case scenarios" is [edit: potentially] better than [just] having higher AC. Just pretend I said "Since the AED reduction of having higher GDR is extremely similar to just having somewhat higher AC."

[mps]

Here's a wild idea: How about make all damage reduction gauranteed damage reduction? It was never a good idea to randomize the value of armour in the first place, so get rid of that, set damage reduction to half of AC (or less if necessary) and do some fsim to get average combat outcomes to look roughly like the old ones on average, tweaking AC values from base armour types and skill over the course of a few versions of trunk.

This approach could be profitably applied to many of the rolls involved in combat resolution. Multiply by (2500 + 1d(100*weapon skill))/2 -- how about multiply by (2500 + 50*weapon_skill)/2?

[wheals]

It was never a good idea to randomize the value of armour in the first place

What is the issue? Maybe that AC is too similar to EV with randomness, but I haven't really heard that said. It's not confusion for new player -- at least, I haven't seen anyone being confused about it. Guaranteed damage reduction sort of works in ADOM, say, because criticals exist, but your system would mean yaks would never ever hurt someone with a "DR" of 18. And even there, it makes melee really boring, until you suddenly come across an effect that ignores PV and it becomes really dangerous.

If you just want to complain about randomness in crawl combat, well, there's another thread for that.

[duvessa]

"Here's a wild idea: how about something completely and utterly unrelated to the topic"?

The OP's point, and the point of the thread, is about (I think) trying to give people all the information they need to make decisions. It is a very unusual case indeed where having the knowledge of GDR and how it works will actually lead you to alter a decision. However, it remains a game mechanic that is prone to being misunderstood, when people do hear about it. So basically the game should either stay as it is now, or else change GDR. Giving the player the GDR value, with no additional information, would be actively misleading. Trying to explain what the GDR value actually means would be drawing even more attention to something that very rarely matters in terms of actual game play decisions. Ergo, GDR should be changed/removed, or else the current (no documentation) status quo, whatever the problems with it, should be retained.

I disagree. While GDR can basically never affect decisions, I don't think it would be actively harmful for the game to explain it, so long as it did so correctly; in fact I think it would be better than the current situation. I just don't think I could ever convince the devteam to do so, and campaigning to remove it is better anyway because it's a dumb mechanic in my opinion.

[mps]

It was never a good idea to randomize the value of armour in the first place

What is the issue? Maybe that AC is too similar to EV with randomness, but I haven't really heard that said. It's not confusion for new player -- at least, I haven't seen anyone being confused about it. Guaranteed damage reduction sort of works in ADOM, say, because criticals exist, but your system would mean yaks would never ever hurt someone with a "DR" of 18. And even there, it makes melee really boring, until you suddenly come across an effect that ignores PV and it becomes really dangerous.

If you just want to complain about randomness in crawl combat, well, there's another thread for that.

It's normal for low level popcorn monsters not to be able to do significant (or any) damage to high level characters. It would not be a design flaw if it became literally impossible for yaks to kill a high level melee character at some point. It's not that far from being true already.

The issue is that you have a complicated system that depends in a crucial way on high variance random numbers. It is impossible for players to determine the impact, even approximately, of AC or GDR beyond "more is better" without running combat simulations, which people are fond of saying give a poor representation of how crawl combat actually works. And it's true, of course: short term combat outcomes have little to do with the averages you'll get out of combat simulation, but as you say, that's another matter.

I mean look at the thread, people are saying apparently without irony that GDR makes no real difference. Clearly it makes a difference. It's just too complicated to formulate simple prescriptions about it.

@duvessa: "here's a wild idea: tie GDR to hp."

[Zeke]

While GDR can basically never affect decisions, I don't think it would be actively harmful for the game to explain it, so long as it did so correctly; in fact I think it would be better than the current situation. I just don't think I could ever convince the devteam to do so, and campaigning to remove it is better anyway because it's a dumb mechanic in my opinion.

Removing it will make the game harder that's for sure. I'm not convinced it's stupid.

[edgefigaro]

I want to highlight these two statements.

The OP's point, and the point of the thread, is about (I think) trying to give people all the information they need to make decisions. It is a very unusual case indeed where having the knowledge of GDR and how it works will actually lead you to alter a decision. However, it remains a game mechanic that is prone to being misunderstood, when people do hear about it. So basically the game should either stay as it is now, or else change GDR. Giving the player the GDR value, with no additional information, would be actively misleading. Trying to explain what the GDR value actually means would be drawing even more attention to something that very rarely matters in terms of actual game play decisions. Ergo, GDR should be changed/removed, or else the current (no documentation) status quo, whatever the problems with it, should be retained.

As the OP, I am not so concerned with being aware of specific numbers, rather, I just want to be aware that the mechanic exists at all, and if I want to do further reading, I can poke through the wiki. As an aside, I like the concept of GDR, which is a small subtle mechanic that helps heavily armored melee characters in melee combat when they need it the most. However, I'm not here to be a proponent for GDR as a mechanic, simply that if the mechanic is worth keeping, it should be significant enough to be documented somehow. I do not need actual numbers in the documentation, as they would likely serve to obfuscate rather than clarify.

My position is likely stated better in the following:

From the learndb (https://crawl.develz.org/wiki/doku.php? ... 0.16_plans):

GDR reform — an invisible number. if it's significant, it should be exposed to the player in some way. (“plate armour provides somewhat more protection against melee attacks than a choko”…?) It might be nice to simply associate it directly with AC, or remove it altogether, but there are significant balance considerations involved. this is not going in 0.16, sadly.

I think this is a succinct explanation of the slightly broader aspects of GDR and crawl, and would like to wholeheartedly agree with it. I am happy to let this thread serve as this discussion ground which is what the posters are already doing.

Thank you for the discussion. I have learned much from this thread, and am glad I asked for clarity.

[Sandman25]

I am not sure GDD is correct place for the question but why can't we remove GDR? Characters in light armour don't care about GDR at all, characters in medium armour have spells and EV, characters in heavy armour are already the most powerful (defense-wise) characters and can take the nerf.

[tasonir]

How about adding this simple line to armor descriptions:

Armors with base AC higher than 2 provide some additional protection against being hit by maximum monster damage in melee, which increases the further the base AC exceeds 2.

It's a bit of a long sentence, but it's still one sentence, and could fit into armor descriptions. You could optionally put it on robes/animal skins or not.

[duvessa]

it also tells players nothing

[Wahaha]

I've heard people saying it's noticeable but I've played a lot of robed Nagas and never really noticed it. Then again, I am not very attentive!

I noticed a difference the two or three times I played a ~high AC draconian and fought ettins.

[bananaken]

It's a problem that GDR is already documented through the wiki and other sources. At least that's how I learned about it. Just reading:

GDR is a form of insurance against poor AC rolls;
...
For example, let's say you have 50% GDR and 50 AC, and you're facing an opponent capable of dealing up to 50 damage in a single hit. This would give you a guaranteed damage reduction of 25, taking full advantage of the 50% GDR.

Would send most players brainstorming armor choices with different GDR values since they *are* documented, it's just outside of the game. Despite it also documenting what it *doesn't* affect and how GDR is not magic pixie dust, the examples still make a strong case for at least considering GDR in your armor choices. I reckon I'm not the only one who got this impression, either.

Anyhow, I think if the existing documentation *outside* of the game got improved it would at least be a start. It's already out there anyway, and this way less people would get the impression that GDR is God's gift to armors.

[XuaXua]

What if, instead of being based on armour, GDR was based on "amount of AC from a single source". For every X of AC an armour (or Ring of Robustness, for example) supplies, you get X amount of GDR. This would make it so that high sources of AC provide GDR, but low sources of AC (+2 Gloves) do not provide GDR (or provide very little, stackable, GDR). In this sense, it becomes a more tangible mechanic, worthy of being documented. Additionally, this would allow potential GDR to be increased by enchanting high-enchantment-capacity armour.

edit: amount. not aut)

[bananaken]

What if, instead of being based on armour, GDR was based on "amount of AC from a single source". For every X of AC an armour (or Ring of Robustness, for example) supplies, you get X aut of GDR. This would make it so that high sources of AC provide GDR, but low sources of AC (+2 Gloves) do not provide GDR (or provide very little, stackable, GDR). In this sense, it becomes a more tangible mechanic, worthy of being documented. Additionally, this would allow potential GDR to be increased by enchanting high-enchantment-capacity armour.

Huh, you gain X Arbitrary Units of Time of GDR?

That kind of implementation could help balance out classes that can't wear body armour to get GDR, sure. Heck, why not just simplify it so GDR is just tied to total AC? The claim is that GDR doesn't usually affect armor decisions, so in that case "merging" GDR with AC should align with the game's intended defense stat management of just AC/EV/SH. That still leaves the problem of rewriting/balancing GDR, but as long as the intention is:

GDR is a form of insurance against poor AC rolls;

Then it should be pretty easy to reformulate based on total AC.

[njvack]

Personally I'd like it if GDR were removed (and armour base AC, statue/dragon form buffed a bit) because it's weird in so many ways

I'd like it if GDR were removed because eventually these threads would stop happening. Seriously, they come up in GDD and Advice and CiP and for all I know everywhere else, too. There's probably a Crawl GDR subreddit.

Even if there were just an empty Git commit and changelog entry saying GDR was gone, that would probably solve the majority of the problem.

[XuaXua]

Heck, why not just simplify it so GDR is just tied to total AC?

Because in the current system, GDR is tied to sources of large values of AC. Currently, you may gain AC from a variety of sources (spells, mutations, armour, aux armour, jewelery), but it is only body armour that gives GDR.

In the proposed system, any source that can provide a large value of AC (for example, an item that can potentially provide +5(?) or more AC; the "AC Threshold"), GDR can be sourced; GDR would have a value based either on the potential AC maximum of that source, or based on the current AC provided by the source, stackable with other sources of GDR.

In this sense, wearing a Ring of Robustness, Ring Mail (possibly of a certain enchantment) and having a spell cast that provides AC at Threshhold has 3 sources of GDR. Non-artefact aux armour and most AC mutations won't pass the AC Threshold necessary to provide GDR. Artefact Aux could certainly add GDR if they pass the Threshold.

This would give an incentive to wear single large AC sources over piecemeal AC sources.

[mattlistener]

it is only body armour that gives GDR.

Also Statue Form, Dragon Form, and being a Gargoyle.

[XuaXua]

Also Statue Form, Dragon Form, and being a Gargoyle.

These also have the added bonus of being sources of large AC values (Gargoyle initially and over time), which would fit with the "large single source of AC = GDR source" concept.

[bananaken]

it is only body armour that gives GDR.

Also Statue Form, Dragon Form, and being a Gargoyle.

You're right, I was trying to talk about GDR among pieces of armor and jewelry only but I should have included "outside" sources of GDR.

This would give an incentive to wear single large AC sources over piecemeal AC sources.

Maybe I'm misunderstanding something, but it doesn't sound like development is considering changes to GDR that would affect your armor wearing decisions based on more potential GDR. If GDR is tied to AC somehow, it'd be done seamlessly so you just keep balancing AC/EV/SH. Other than that, yeah I think it's certainly a possibility.

TBH, I don't feel strongly about GDR remaining as-is, being tied to equipment AC, or being removed altogether. That said, I think combining GDR and AC into just total AC sounds like a pretty simple solution (even if rebalancing appropriately is not simple) and aligns with the goals of keeping GDR as something that shouldn't be considered, all while having a way to protect the player from poor rolls against melee attacks. Depending on how it's implemented it could be a non-trivial buff to characters that don't have access to body armor GDR. As far as existing spells and races that add GDR, they could be rebalanced to just add more AC instead of GDR. It's probably going to need some math.

e: edited for clarity

[kuniqs]

For every point of 'base AC', you get 2 points of X. Total X adds up to GDR2

GDR2 works like this: For each point of melee damage, there's a %GDR2 chance to negate it.

So, a character wearing gloves (1 bAC), crystal plate mail (14 bAC), helmet (1 bAC), boots (1 bAC) and cloak (1 bAC) has 36 GDR2.


For something completely different: Is acid damage reduced by rCorr in 0.16? Does having more equipment slots filled still reduces acid damage in 0.16?

For something completely different2: Is there a DCSS monster database somewhere, where I could query for, say, a list of monsters sorted by their AC?

[tasonir]

As far as I know, slots being filled still reduces acid damage, but I may be mistaken.

I'm not sure about being able to query them by property, but probably the bots in the IRC channel would be your best bet. You can certainly query for monster stats, I just don't know about sorting/getting more than one monster at a time. Hell sentinels have 25 ac, orbs of fire/ancient liches have 20, so do emperor scorpions. Those are among the highest AC monsters I know of, not counting uniques. Cerebov/Tiamat have 30, Dispater has 40, etc.