
pad300 |
Ok, the party has snuck up on a sleeping dragon. They can't get too close because they would trigger blindsense and it would wake up. So they are thinking about starting with a volley of missiles against sleepyhead...
Rules Q.
Is there a bonus for shooting at a sleeping target? When I look through the combat rules, all I find is a -4 for ranged attack at a prone target (a gargantuan dragon for Chrissake!). It's not losing a dex bonus. (The dragon's dex bonus is actually a penalty, -2. Does it actually lose that penalty and improve it's AC there as well?) Would they actually be better off (effective +6 to hit) shooting at it when awake? That seems wrong...

Lemartes |

A helpless character is paralyzed, held, bound, sleeping, unconscious, or otherwise completely at an opponent’s mercy. A helpless target is treated as having a Dexterity of 0 (–5 modifier). Melee attacks against a helpless target get a +4 bonus (equivalent to attacking a prone target). Ranged attacks get no special bonus against helpless targets. Rogues can sneak attack helpless targets.
So -5 for dex as well as losing any dodge bonuses or the alike, therefore -5 dex mod and +4 for being prone vs range attacks for a total of -1 AC.
Or in other words the attackers are +1 to hit the dragon at range. Ignoring any possible range penalties. :)
Edit: Actually I think I got that wrong. It's hard without the actual full stats. Lets assume a the AC is 10 then 8 after it's dex when awake. So sleeping it would be 5. So three easier. Then calculate +4 to AC vs range attacks due to being prone.
So they would be actually -1 to all range attacks(prone and sleeping) VS -4 with it awake and prone. :)

Talonhawke |

I mean they are unconcious when sleeping I would assume. So that applies Unconscious creatures are knocked out and helpless.
Unconsciousness can result from having negative hit points (but not more than the creature’s Constitution score), or from nonlethal damage in excess of current hit points.
A helpless character is paralyzed, held, bound, sleeping, unconscious, or otherwise completely at an opponent’s mercy. A helpless target is treated as having a Dexterity of 0 (–5 modifier). Melee attacks against a helpless target get a +4 bonus (equivalent to attacking a prone target). Ranged attacks get no special bonus against helpless targets. Rogues can sneak attack helpless targets.
As a full-round action, an enemy can use a melee weapon to deliver a coup de grace to a helpless foe. An enemy can also use a bow or crossbow, provided he is adjacent to the target. The attacker automatically hits and scores a critical hit. (A rogue also gets his sneak attack damage bonus against a helpless foe when delivering a coup de grace.) If the defender survives, he must make a Fortitude save (DC 10 + damage dealt) or die. Delivering a coup de grace provokes attacks of opportunity.
Creatures that are immune to critical hits do not take critical damage, nor do they need to make Fortitude saves to avoid being killed by a coup de grace.[/quote}

LordKailas |

If the dragon is asleep it would actually have the helpless condition
A helpless character is paralyzed, held, bound, sleeping, unconscious, or otherwise completely at an opponent’s mercy. A helpless target is treated as having a Dexterity of 0 (–5 modifier). Melee attacks against a helpless target get a +4 bonus (equivalent to attacking a prone target). Ranged attacks get no special bonus against helpless targets. Rogues can sneak attack helpless targets.
now, Assuming it's also prone it would suffer the penalties/bonuses as normal (I believe the line about prone is just so you don't double stack the penalties).
The character is lying on the ground. A prone attacker has a –4 penalty on melee attack rolls and cannot use a ranged weapon (except for a crossbow). A prone defender gains a +4 bonus to Armor Class against ranged attacks, but takes a –4 penalty to AC against melee attacks.
So, the -2 from dex would go to a -5, but the dragon gets a +4 for being prone against ranged attacks. So, it would be a net gain of +1 to AC vs it standing up and being awake.
If the party had some way to be adjacent they not only would get a net +7 to hit (with melee), but they could even coup de grace the dragon for a possible instant kill with the weapon of their choice (including the bow).
Edit: apparently there were a bunch of responses between when I hit reply and when I finished copying/pasting and formatting my post. So, yes the dragon does have a higher AC. But if it makes you feel any better it would be even higher if it were awake and prone vs standing.

LordKailas |

Uh... that's an interesting tid-bit... should a dragon really get a prone bonus or penalty to AC if the target is huge compared to a human?
Very interesting philosophical / rules question...
I certainly hope so, since being Huge already applies a -2 penalty to their AC and their bonus to hit. If a huge creature can't be prone then it also can't be tripped. I'm not sure why that should be the case just because it's very big.
Imagine for a moment you have a catapult that you are shooting at Godzilla. It makes sense that you will have a "slightly" harder time hitting Godzilla if he's crouching/laying down vs standing at his full height. The dragon is no different.

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Yeah, if I were shooting from a long range. Absolutely, rules accounts for range increments. However there is in the core rulebook an entry for ignoring certain cover (I believe soft cover or when shooting into melee with friendly) or AC bonuses if an enemy is bigger than the attacker. I think it was a two size difference thing. Also distance is also taken into a factor in a cover with height situation.
So RAW yeah, I think you are right. RAI should... doesn't really matter as it's not a confusion of rules. Instead it is a deficiency in the prone rules. It's like shooting someone a prone medium sized creature point blank(adjacent)... In reality there shouldn't be a penalty, as the silhouette of the person is not reduced at that point, but rules don't account for that.

Quixote |

...should a dragon really get a prone bonus or penalty to AC...?
I certainly hope so, since being Huge already applies a -2 penalty to their AC and their bonus to hit. If a huge creature can't be prone then it also can't be tripped. I'm not sure why that should be the case just because it's very big.
Imagine for a moment you have a catapult that you are shooting at Godzilla. It makes sense that you will have a "slightly" harder time hitting Godzilla if he's crouching/laying down vs standing at his full height. The dragon is no different.
There's a pretty big difference between being immune to the prone condition and not benefitting from all the aspects of the prone condition. If a target is sufficiently large and you're sufficiently close enough, I can easily see them getting less of the bonus for being prone, up to none (if, say, you still have to aim your shot upwards, I wouldn't really consider them benefitting from being prone).
By RAW, your dragon's AC versus ranged attacks is 1 higher while asleep and prone. But if you want to reward your players for their decisions, hand-wave it. I know I would

LordKailas |

There's a pretty big difference between being immune to the prone condition and not benefitting from all the aspects of the prone condition. If a target is sufficiently large and you're sufficiently close enough, I can easily see them getting less of the bonus for being prone, up to none (if, say, you still have to aim your shot upwards, I wouldn't really consider them benefitting from being prone).
What about melee attacks?
normally, when making a melee attack against a prone creature you get a bonus to hit. If you're saying the creature is so large that it doesn't matter if it's prone or not with regard to ranged attacks I assume it similarly wouldn't matter about melee attacks either.
I feel like what's getting lost is that creatures get a bonus or penalty to their AC based purely on size. A colossal creature gets a -8 to it's AC, while a fine creature gets a +8.
For example. Creature A and Creature B are medium size and Creature A has a +0 to hit Creature B. Now you make creature A tiny and creature B Huge (without any stat adjustment). Creature A effectively gains a +4 to hit creature B from the size change alone.
As for being close, its true that IRL it is easier to hit a target when it's at point blank range. Unfortunately, in pathfinder characters do not receive any bonus to hit for being at point blank range unless they've taken the feat point blank shot. So, (assuming you have the feat) you already get a bonus to hit an enemy that is sufficiently close regardless of anything else.
If you want to house rule that ranged attacks only suffer a penalty to hit prone targets if they are more than 30 feet away that's fine. After all, if someone is laying on the sand 10 feet away from me my chances to hit them probably don't change that much since the visible area of their profile is the same as when they are standing up. The same is true regardless if they are medium, colossal, or fine at that distance.
edit: Just keep in mind that any sort of ruling that favors smaller creatures attacking larger creatures, will simultaneously nerf larger creatures defense, while boosting smaller creatures offense. A tiny creature already gets +2 to hit a medium sized creature. If going prone doesn't help a huge creature against a medium creature, going prone similarly wouldn't help a medium creature against a tiny creature.

Quixote |

What about melee attacks?
I've always been under the impression that the penalty to hit at ranged was a sort of pseudo-size penalty, where as the bonus to hit in melee was more of an anti-dodge.
...you're saying the creature is so large that it doesn't matter if it's prone or not with regard to ranged attacks...
I am not. I am saying that, in certain situations, I can see how the penalty may be reduced or negated.
Specifically in this one with the sleeping gargantuan dragon, I see no reason to penalize a group of players who have been clever enough to sneak up on a dragon. I mean, it's asleep. Just draw, aim and loose. It's not going anywhere.I feel like what's getting lost is that creatures get a bonus or penalty to their AC based purely on size.
I can assure you, that's not "getting lost here". I was only saying that, in a game where the rules are encouraged to be bent, changed, broken or ignored, I see no reason to tell a group of players that the dragon is harder to hit when it's sleeping then it is when it's awake. They've got nothing but time to line up their shots. They've made it this far. I'll give them something, even if it's only an effective +1 to hit.
If you want to house rule that ranged attacks only suffer a penalty to hit prone targets if they are more than 30 feet away that's fine.
Sure. I don't, though. I want to be flexible and make adjustments as I go, to ensure the most dynamic, engaging, memorable and moving story I can. So. In this specific case, I'd give the party...maybe a total of +2 to hit with that first volley. Same as if they were invisible. They can line up their shots and hit the thing 100% of the time, but those scales are still a big issue. Hopefully that's enough to make the players feel like their decisions matter.
But RAW, no. +1 AC. Because a sleeping 85ft monster is a more elusive target than a conscious one.

Talonhawke |

The prone thing is to take into account that the creature is typically in a pose that makes a ranged shot harder due to a number of factors.
1. Different posture
2. Possibly more compressed mass.
3. different angle to hit than normal.
And for anything going prone makes them harder to hit, not just big ones. Their size is already factored into their AC as a penalty no need to factor it in twice.

Quixote |

After all, if the dragon were awake and laying down it'd have a +4 instead of a +1.
Sure. I'd be fine with a dragon tactically choosing to go prone, for some reason.
The prone thing is to take into account...
Maybe. I don't presume to know the RAI.
Personally, it always made the most sense to consider the prone modifier as a sort of size one.But again, I don't think a sleeping target should be harder to attack than one that's awake.
I wouldn't even really feel the need to change the prone modifier, specifically. Just hand out a decent enough "aiming" bonus to make it a little easier.

Talonhawke |

But again, I don't think a sleeping target should be harder to attack than one that's awake.
It's not asleep it has a -5 AC from Dex and a +4 from prone for a net -1. Awake it only has it's -2 dex and +4 from prone for a net +2. So it is harder to hit awake than it is asleep.
Now true that awake and upright it is easier to hit but again the rules are simulating how any number of unspecified changes to shape/positioning/angle/etc. from going prone make it harder to shoot at range but those rules apply to anything. And as weird as it is anything with a Dex lower than 8 dex does suddenly get harder to hit asleep because it has less actual dex to lose.

LordKailas |

And as weird as it is anything with a Dex lower than 8 dex does suddenly get harder to hit asleep because it has less actual dex to lose.
Probably the easiest way to think about a dex less than 8 is that it isn't that the creature is clumsy, it's that it has a really slow reaction speed. As a result a creature with a dex of 3 laying on the ground practically has the same AC regardless if it's sleeping or awake.
So, in the original example the dragon is so bad at reacting to things that it's literally better off laying low and not moving at all than if it stood up and actually tried to dodge.

Quixote |

It's not asleep it has a -5 AC from Dex and a +4 from prone for a net -1. Awake it only has it's -2 dex and +4 from prone for a net +2. So it is harder to hit awake than it is asleep.
Im not sure if I followed that first part at all, but I'm pretty sure I got the jist.
And once again, I am well aware of how the rules work, thank you. I know how AC is calculated. I performed the same basic math a few posts above in this very thread.
My point is, again, that IN THIS SPECIFIC SITUATION, a sleeping target is more difficult to strike than one that is awake and walking around.
I understand why, by the RAW, this is the case, and I probably have as good of a chance as any to guess at why the rules are as they are and what they represent.
But in my opinion, the rules fall a little short IN THIS SPECIFIC SITUATION, and I, if it were me running this game, would like to reward my player's s clever decisions with some kind of reward, even if it's something as paltry as a +2 bonus for one round.
And hey, that's just my opinion. Run it as close to the RAW as you like. Do away with Rule Zero and play the game like you would Monopoly or Battleship. I'm sure there's something to be said for consistent rulings in many groups.

Talonhawke |

I was pointing out that any any situation where Dex < 8 then a sleeping target will be harder to hit. Size doesn't matter a sleeping orc with 8 dex will be harder to hit with a bow than if he is standing. The only reason your having issues is because you believe the target should be penalized twice for it's size.
If this huge creature had a 20 dex and was now losing 10 AC and only getting 4 back we wouldn't still be arguing that it's a problem because it would in fact be easier to hit.
No one is saying you can't adjust the rules at all, we are in fact agreeing that by the rules its a bit odd that these creatures are harder to hit. But again if this situation was with a high dex creature or a smaller one like an orc it likely wouldn't be raising your ire in the least. If you the DM want to give them a bonus to hit or ignore the prone penalty you can, but when you make those adjustments you need to think on why and what else down the road might be affected.

Talonhawke |

I'm sure there's something to be said for consistent rulings in many groups.
Wanted to address this separately, there is a lot to be said for consistent rulings. It lets the players have a baseline that they can expect to work from. If when the players are sleeping the tiny enemy gets to ignore the bonus from prone then they would expect the same later on. If you rule that a creature x sizes larger than the target gets a free bull rush on melee attacks they would expect the same. Rule 0 is great I've used it many times, but when I do I make sure it's applied consistently and I make sure my players know whats being changed and why.
I've played in games where it was anything goes as long as you can convince the GM. And for some things like using your shield as an improvised sled sure. But when the GM likes the idea of feather fall being cast makes the target immune to the momentum of incoming arrows, or Paladins can't attack a flat-foot target or they fall these don't bring anything to the table and it's even worse when it comes up mid-session and no one told you.

Quixote |

...you believe the target should be penalized twice for it's size.
Please do not tell me what I believe or assign motivation to my actions.
If this huge creature had a 20 dex and was now losing 10 AC and only getting 4 back we wouldn't still be arguing that it's a problem because it would in fact be easier to hit.
...yes. Agree 100%. If my PC's manage to attack a sleeping target, especially one as potent and wily as a true dragon, I think they ought to get a little something for it.
And again, it's less about the target's size or dexterity and more about the time you'd have to sit there, control your breathing, wait for a favorable wind, etc. Instead of looking up some oddball 3rd party/supplemental aiming mechanics, I'd just pass out a small bonus and keep the encounter moving.As I've said, I can see certain situations where the prone modifier could be altered or waived. But those are few and far between. A gargantuan dragon should still be able to get some kind of cover from missile fire. But strategically seeking cover and taking a nap are different situations, thematically.
...you need to think on why and what else down the road might be affected.
Agreed. I would never suggest hacking the system without good reason. "Because it just makes me sense" is a trash reason. This is a game. Gameplay should be the #1 focus.
If when the players are sleeping the tiny enemy gets to ignore the bonus from prone then they would expect the same later on. If you rule that a creature x sizes larger than the target gets a free bull rush on melee attacks they would expect the same.
Unless the previous encounter/creature was a unique situation. In my experience, a GM who demonstrates enough system mastery and player advocacy is given pretty much as much leway as they need. My players trust my off-the-cuff decisions to be fair ones, even if they're not always mechanically the same as the previous ones. Though that is probably due in large part to no one feeling so disatisfied that they start keeping track.
I've played in games where it was anything goes as long as you can convince the GM...these don't bring anything to the table and it's even worse when it comes up mid-session and no one told you.
Yeah, that sounds awful.
My games are always homebrewed, houseruled to the point where we can barely claim to be playing the actual system anymore. But that is all stuff that's discussed at session 0.
Scott Wilhelm |
Ok, the party has snuck up on a sleeping dragon. They can't get too close because they would trigger blindsense and it would wake up. So they are thinking about starting with a volley of missiles against sleepyhead...
Rules Q.
Is there a bonus for shooting at a sleeping target? When I look through the combat rules, all I find is a -4 for ranged attack at a prone target (a gargantuan dragon for Chrissake!). It's not losing a dex bonus. (The dragon's dex bonus is actually a penalty, -2. Does it actually lose that penalty and improve it's AC there as well?) Would they actually be better off (effective +6 to hit) shooting at it when awake? That seems wrong...
I was just looking at Blindsense, Sleep, and Helpless, and I don't see how Blindsense gives anyone the ability to wake up when asleep and approached by sneaky people. What I found by way of rules for waking up when someone is sneaking up on you while asleep is in the Perception Skill. There are DCs for hearing a whispered conversation, hearing a bow being drawn, noticing a visible creature, hearing a creature walking, turning a key in a lock etc. And there is a +10 on the DC when the perceiver is asleep.
It seems to me that the party should be able to sneak up on and coup de grace a sleeping dragon with Stealth Checks opposed to the Dragon's perception check, and the party all get +10s because the Dragon is asleep.

LordKailas |

I was just looking at Blindsense, Sleep, and Helpless, and I don't see how Blindsense gives anyone the ability to wake up when asleep and approached by sneaky people. What I found by way of rules for waking up when someone is sneaking up on you while asleep is in the Perception Skill. There are DCs for hearing a whispered conversation, hearing a bow being drawn, noticing a visible creature, hearing a creature walking, turning a key in a lock etc. And there is a +10 on the DC when the perceiver is asleep.
It seems to me that the party should be able to sneak up on and coup de grace a sleeping dragon with Stealth Checks opposed to the Dragon's perception check, and the party all get +10s because the Dragon is asleep.
I'm not sure what version of blindsense you looked at. You are correct there is a perception check. Blindsense says the following.
Blindsense lets a creature notice things it cannot see, but without the precision of blindsight. The creature with blindsense usually does not need to make Perception checks to notice and locate creatures within range of its blindsense ability, provided that it has line of effect to that creature.
IMO I think it's a little BS that a sleeping dragon would automatically wake up if something comes within it's blindsense range, but so far as I can tell it's a valid interpretation of the ability.

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Scott Wilhelm wrote:I was just looking at Blindsense, Sleep, and Helpless, and I don't see how Blindsense gives anyone the ability to wake up when asleep and approached by sneaky people. What I found by way of rules for waking up when someone is sneaking up on you while asleep is in the Perception Skill. There are DCs for hearing a whispered conversation, hearing a bow being drawn, noticing a visible creature, hearing a creature walking, turning a key in a lock etc. And there is a +10 on the DC when the perceiver is asleep.
It seems to me that the party should be able to sneak up on and coup de grace a sleeping dragon with Stealth Checks opposed to the Dragon's perception check, and the party all get +10s because the Dragon is asleep.
I'm not sure what version of blindsense you looked at. You are correct there is a perception check. Blindsense says the following.
Blindsense wrote:Blindsense lets a creature notice things it cannot see, but without the precision of blindsight. The creature with blindsense usually does not need to make Perception checks to notice and locate creatures within range of its blindsense ability, provided that it has line of effect to that creature.IMO I think it's a little BS that a sleeping dragon would automatically wake up if something comes within it's blindsense range, but so far as I can tell it's a valid interpretation of the ability.
I will not give it an automatic success. As a minimum, I will require the dragon to make a perception check with a base of 0 and a +10 for being asleep (blindsense would negate most invisibility related modifiers).
So high stealth characters have a chance to attack the sleeping dragon, but, taking into consideration the typical perception of dragons, the majority of the characters will be detected.Blindsense can be a lot of things, from sensibility to ground vibrations to a very developed sense of smell to an undefined sixth sense, so it is a matter of GM adjudication and taste.

Melkiador |
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Being prone also implies that a lot of the creature’s vitals are covered by the ground. So, it’s not just that it’s a smaller target, but there are also fewer deadly places to hit.
A melee attack generally has more force, so doesn’t rely as much on hitting the “right” spot. And it can even make the hit be harder since you are getting them between the hard ground and your hard weapon.

Scott Wilhelm |
Scott Wilhelm wrote:I was just looking at Blindsense, Sleep, and Helpless, and I don't see how Blindsense gives anyone the ability to wake up when asleep and approached by sneaky people. What I found by way of rules for waking up when someone is sneaking up on you while asleep is in the Perception Skill. There are DCs for hearing a whispered conversation, hearing a bow being drawn, noticing a visible creature, hearing a creature walking, turning a key in a lock etc. And there is a +10 on the DC when the perceiver is asleep.
It seems to me that the party should be able to sneak up on and coup de grace a sleeping dragon with Stealth Checks opposed to the Dragon's perception check, and the party all get +10s because the Dragon is asleep.
I'm not sure what version of blindsense you looked at. You are correct there is a perception check. Blindsense says the following.
Blindsense wrote:Blindsense lets a creature notice things it cannot see, but without the precision of blindsight. The creature with blindsense usually does not need to make Perception checks to notice and locate creatures within range of its blindsense ability, provided that it has line of effect to that creature.IMO I think it's a little BS that a sleeping dragon would automatically wake up if something comes within it's blindsense range, but so far as I can tell it's a valid interpretation of the ability.
You should still be able to make a Stealth check, though. Stealth is not all about not being seen, but also about being heard, and Blindsense depends a lot on hearing. What Blindsense does is negate the ability of Invisible creatures to hide their location. It doesn't automatically wake you up when someone is there. That's all I'm saying.
As a minimum, I will require the dragon to make a perception check with a base of 0 and a +10 for being asleep (blindsense would negate most invisibility related modifiers).
That being said, a Dragon's Perception Bonus can run high.
Adult Red Dragon: +23
Black: +24
Blue: 22
White: 22
Still, Silence is only a level 2 cleric spell. Negate Aroma is only a level 1 Ranger Spell. Sneaking up on a Sleeping Dragon should be quite doable with a prepared party.

Scott Wilhelm |
Can you use stealth (normally) to hide from Blindsense ? What's Dampen Presence (Feat) for otherwise?
The creature usually does not need to make Perception checks to pinpoint the location of a creature within range of its blindsense ability, provided that it has line of effect to that creature.
Yeah, I think maybe Lord Kalas is right. The only real effect I found sleep to do is add +10 to Percpetion Checks. Still, I'm not sure that means sleeping creatures automatically awaken. Blindsense doesn't say that.
I guess you would need magic like Silence and/or negate aroma to be sure.

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The source of the dragon blindsense isn't defined, so it is hard to say what will stop or trigger it.
It can detect sounds or smells, but there are animals that detect thermic emission (not seeing IR emission, perceiving difference in temperature with specific organs), magnetic fields, air currents, ground vibration and so on.
Being a dragon he can smell gold, for all we know.
Silence and Negate aroma could help, but, again it is a GM decision, based on the specific creature.

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Being prone also implies that a lot of the creature’s vitals are covered by the ground. So, it’s not just that it’s a smaller target, but there are also fewer deadly places to hit.
A melee attack generally has more force, so doesn’t rely as much on hitting the “right” spot. And it can even make the hit be harder since you are getting them between the hard ground and your hard weapon.
I like this explanation the best.

Quixote |

Melkiador wrote:I like this explanation the best.Being prone also implies that a lot of the creature’s vitals are covered by the ground. So, it’s not just that it’s a smaller target, but there are also fewer deadly places to hit.
A melee attack generally has more force, so doesn’t rely as much on hitting the “right” spot. And it can even make the hit be harder since you are getting them between the hard ground and your hard weapon.
It's interesting, for sure. I don't know how accurate it is (I feel like, in reality, a crossbow can deliver quite a bit more force than a spear-thrust, etc).

Scott Wilhelm |
Yure wrote:It's interesting, for sure. I don't know how accurate it is (I feel like, in reality, a crossbow can deliver quite a bit more force than a spear-thrust, etc).Melkiador wrote:I like this explanation the best.Being prone also implies that a lot of the creature’s vitals are covered by the ground. So, it’s not just that it’s a smaller target, but there are also fewer deadly places to hit.
A melee attack generally has more force, so doesn’t rely as much on hitting the “right” spot. And it can even make the hit be harder since you are getting them between the hard ground and your hard weapon.
Well, if you use the Crossbow the same way you'd use the Greatsword, firing at them from 5', then sure. And one of the things that we are talking about is approaching a sleeping target closing to melee range and coup-de-gracing them. For that purpose, Crossbow works just like a melee weapon, I'm pretty sure.
A Crossbow Bolt might very plausibly have less power when fired 100' away might quite plausibly be less accurate than a Greatword used from 5' away. I guess either might be an unfair comparison depending on how you look at it.
Per RAW, Prone Targets are +4 to be hit in melee, -4 to be hit at Range. I think that is to address the very things you are talking about.

Quixote |

And one of the things that we are talking about is approaching a sleeping target closing to melee range and coup-de-gracing them.
I think the topic of that particular conversation was actually about the reason behind the prone modifiers to AC, not about coup de gras.
A Crossbow Bolt might very plausibly have less power when fired 100' away might quite plausibly be less accurate than a Greatword used from 5' away.
I have no idea. That was my point. I've seen a broad head arrow travel THROUGH several FEET of living flesh. But then, I've seen a cheap "great sword" chop and crush it's way through a bull's skull and a real-deal no dachi slice 27 tatami mats in one go.
Per RAW, Prone Targets are +4 to be hit in melee, -4 to be hit at Range. I think that is to address the very things you are talking about.
I think a much simpler metaphor would be what I stated earlier; prone makes you effectively "smaller" at a distance, but makes avoiding attacks up close significantly harder.