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Old 02-02-2012, 05:01 PM   #1
apoc527
 
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Default Stealth -- does it use JUST MoS or do range penalties apply?

Say a PC is trying to sneak through some woods towards an enemy campfire. Do you care only about his MoS (with modifiers for places to hide etc) or do range penalties apply as well? What about Vision vs Hearing? If it's dark out, enemies will be listening more than watching, so are there penalties to hear a stealthy PC from range or does the PC get a bonus?
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Old 02-02-2012, 05:06 PM   #2
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Default Re: Stealth -- does it use JUST MoS or do range penalties apply?

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Originally Posted by apoc527 View Post
Say a PC is trying to sneak through some woods towards an enemy campfire. Do you care only about his MoS (with modifiers for places to hide etc) or do range penalties apply as well? What about Vision vs Hearing? If it's dark out, enemies will be listening more than watching, so are there penalties to hear a stealthy PC from range or does the PC get a bonus?
Uh...what? The other guys sense rolls are modified by ranged. And no people aren't markedly better listeners at night.
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Old 02-02-2012, 05:12 PM   #3
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Default Re: Stealth -- does it use JUST MoS or do range penalties apply?

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Originally Posted by David Johnston2 View Post
Uh...what? The other guys sense rolls are modified by ranged. And no people aren't markedly better listeners at night.
I will disagree with the latter a bit.
At night it is often quieter, in both city and country so you have less background noise in the way and sound seems to carry farther.
I would probably give a +1 to +3 bonus at night for that, depending on location and circumstance.
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Old 02-02-2012, 06:29 PM   #4
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Default Re: Stealth -- does it use JUST MoS or do range penalties apply?

Vision rolls are always penalized by the speed-range table - things like Telescopic Vision or binoculars offset the penalty or reduce the effective range, but short of something like Clairvoyance to put your "eyes" closer to the target, you never ignore range penalties.

Hearing rolls always take a range penalty.

The details for both of these are on p358 - basically unless you have a power or piece of equipment that says otherwise, if you're rolling against Hearing or Vision, you have range penalties, background noise penalties etc.

You don't get a bonus at night for it being quiet, the baseline is quiet. You get a penalty if there's background noise. Sound doesn't magically bounce off of objects better at night. You're just not distracted.
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Old 02-02-2012, 06:46 PM   #5
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Default Re: Stealth -- does it use JUST MoS or do range penalties apply?

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You don't get a bonus at night for it being quiet, the baseline is quiet. You get a penalty if there's background noise. Sound doesn't magically bounce off of objects better at night. You're just not distracted.
From reading the hearing range table I would really hope that the baseline for hearing is combat or similar.. as "Normal conversation 1" would have a standard human(Per 10) miss 50% of what other human says at normal but not overly loud voice at range of 1 yard in a quiet place.
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Old 02-28-2012, 09:48 AM   #6
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Default Re: Stealth -- does it use JUST MoS or do range penalties apply?

I think Vehicles 3E introduced Mk1 Eyeball, which basically said that your eye's scan rating is +10 under normal circumstances. That is, on average, your basic human will spot another human at 100 yards 50% of the time. Assuming I got that correctly.

I'd be tempted to do the same for human ear as well, although likely a smaller bonus. Definitely should be able to hear a normal discussion in the same room almost all the time, absent of background noise. Maybe something like +5? I do know that I have difficulties hearing what is said a couple of chairs from me in a noisy restaurant, though, so obviously situational modifiers apply (is the person talking towards me or away from me makes a surprisingly big difference!).

Then again, I usually just use 'roll and shout' -method of eyeballing the roll and deciding on the fly rather than dig up formulas when I GM, so...
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Old 02-28-2012, 10:28 AM   #7
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Default Re: Stealth -- does it use JUST MoS or do range penalties apply?

I just read pg 358 and found nothing there stating that the default is quiet or normal daytime. Having said that, I considered the ranges given in the Hearing Distance Table and decided that the baseline is not quiet. The ranges gives are at no penalty. A normal conversation at 3 feet (1 yard) is about right if there are distracting noises.
It also mentions that if the people are actively trying to hear something then the GM can use Observation instead of Perception. Under that skill are listed modifiers but no modifier given for quiet or normal noise.
So, I would say that at night there would be a small bonus, especially for someone with a background that reflects knowledge of the forest at night, and that range modifiers would count.
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Old 02-29-2012, 07:42 AM   #8
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Default Re: Stealth -- does it use JUST MoS or do range penalties apply?

This is how I handle Stealth. I'd be delighted to get feedback from the forum community. While this is a house rule, my intention is not to go against the RAW, simply add detail. So, if anything here is actually against the rules, do let me know.

HOUSE RULE: Stealth
This house rule adds a quantifiable component to how close you can sneak up on someone.
Stealth
DX/Average
Defaults: DX-5, or IQ-5
Stealth vs Perception
The GM will use the result of the Quick Contest between Stealth and Perception and apply the results to the Size and Speed/Range Table [B550] to determine at what distance the stealthy person is seen and/or heard. Since the Stealthy person will know how good their roll is, they will have an informed opinion when they tell the GM how close and how quickly they intend to approach their quarry. If they chose a distance that is not too close, then they will not be detected; if they choose a distance that is too close, then they will be detected the moment they step into the range determined by the Size and Speed/ Range Table [B550]. On a tie, the quarry has noticed something (heard a twig snap, caught movement out of the corner of their eye, etc.) and can react, but will not know the source of the disturbance.

After the Stealthy person makes a roll, they must move one or more hexes towards their intended target. Assuming they were not discovered, they can then request another Quick Contest (at no penalty for a repeated attempt). Thus, a Stealthy person can break up their approach into more than one Quick Contest if that is to their liking.

Modifiers
In some cases, it's not obvious if a modifier should be applied to the Stealth roll or the Perception roll. Whatever is decided, be sure not to double dip.
  • a penalty equal to your encumbrance level
  • -5 to fool those with Discriminatory Smell, usually animals (unless you are downwind of them)
  • darkness penalties will affect vision rolls

Environmental Modifiers
  • a +10 if they're in an enclosed structure, e.g. they're on the other side of a closed door
  • +5 if they can't possibly see you, e.g. their back is to you
  • +3 for many hiding places, e.g. stalking game in a forest where tree trunks will hide you
  • -3 for an area void of ambient noise, e.g. inside a empty building, no a/c, no fluorescent lights,
    isolated from outside street noise
  • -5 an area without "natural" hiding places, e.g. stalking someone down the hotel hallway
  • -10 a bare area with no shadows, e.g. a clearing in the woods or an empty room

Movement Modifiers
  • a penalty equal to your move-1 (i.e. no penalty if you're moving 1 yard/sec)
  • +3 if you're move is 0, but you are still active, e.g. staying put but took a Ready maneuver
  • +5 if you're move is 0, and you are effectively motionless and silent, e.g. staying put but took an Aim
    maneuver
  • +10 if you're move is 0, you're completely hidden and not observing your foe, i.e. you're just plain
    hiding

Examples
Sentry Removal
Corporal Lee Linda wants to sneak all they way up to a guard who is guarding the door to an enemy safe-house. It is night; the guard and door are dimly illuminated but the rest of the surrounding area isn't. The guard is 5 yards from the corner of the building. Lee's Stealth is 13; the sentry's Perception is 11. Lee informs the GM he wants to use Stealth to sneak up to the guard, so situational modifiers are assessed. Since Lee will approach from the side of the building, where the guard can not possibly see him, he'll be at a +5 until he rounds the corner. Once he rounds the corner, he'll be in a bare area, a -10 penalty; but it's dark, so the GM decides a net penalty of -5 is appropriate.

Lee sets out, rolling an 11, a success by 2. Assuming the sentry made his Perception roll exactly and ignoring situational modifiers, Lee would be detected when he got 1 yard from the guard: -2 on the Size and Speed/Range Table [B550]. Applying the -5 penalty after rounding the corner results in a failure by 3. +3 on the Size and Speed/Range Table [B550] means Lee would be detected 7 yards away. Lee thinks he can do better, so he informs the GM he'll move up to the corner of the building. Lee doesn't know this, but the guard also rolled an 11. Since Lee is at a +5 until he rounds the corner, he easily makes it to the corner of the building without being heard.

Having gotten to corner, Lee now rolls to proceed even closer. He'll be at -5 after he rounds the corner. Lee rolls a 9, succeeding by 4, adjusted to failing by 1: 3 yards on the Size and Speed/Range Table [B550]. Lee knows this in not close enough to attack with his Garrote, but he is committed to moving at least one yard closer. Lee informs the GM he'll move only one yard closer this turn. (He's hoping that if he's not detected this turn, he'll be able to All Out Attack him next turn with the element of surprise.) The sentry rolls an 8, succeeding by 3; so Lee actually lost the Quick Contest by 4, resulting in detection at 10 yards. The GM informs Lee that as soon as he rounds the corner, the guard looks over and sees him. (The element of surprise diminished, Lee will be forced to choose between attempting to take him out quietly in hand-to-hand combat, or readying his M4.)

Bow Hunting
Shung Jiao and Shung Li are out bow hunting. Jiao would like to get as close as possible before taking his shot. Li is tracking the wild boar and they are both moving stealthily as the trail seems fresh. They are in the woods and the boar is not downwind of them, so the GM gives them a +3 bonus situational modifier. Shung Jiao's Stealth is 10, Li's is 12; Shung Jiao rolls a 9, Le rolls an 11; they both make their rolls by 1, by 4 with the modifier. They would like to get within 15 yards of the boar. (Shung Jiao's bow skill is 12. Acc 1 with 3 seconds of aiming can increase this to 15. The range penalty at 15 yards is -5.) If they lose the Quick Contest by 4 or less, they're okay. (5 is not okay because then they'd be detected at 15 yards.) They decide this roll is good enough that they've probably not even lost the Quick Contest and commit to approach to 5 yards. Unknown to them, the boar with Perception 12 rolled a 10, succeeding by 2. They won their Quick Contest by 2. The GM informs then they're 5 yards away from a wild boar that is ignoring them. Shung Jiao can now set up his shot. If Shung Jiao decides he wants to move even closer (maybe Shung Jiao decides he wants to staff hunt instead) they will both have to engage in another Quick Contest. Of course, Li will be at +10 since he will choose not to approach with Shung Jiao.
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Old 02-29-2012, 11:27 AM   #9
Bruno
 
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Default Re: Stealth -- does it use JUST MoS or do range penalties apply?

Quote:
Originally Posted by Captain Joy View Post
This is how I handle Stealth. I'd be delighted to get feedback from the forum community. While this is a house rule, my intention is not to go against the RAW, simply add detail. So, if anything here is actually against the rules, do let me know.
This is excellent, although I'd note that Size Modifier of the stealthy person should be a factor in here - I usually assume it's supposed a bonus to the victims Perception roll as part of the general case of using the size modifier as a bonus to see someone or something.

Traditionally the -10 you've applied to Stealth for "In Plain Sight" is applied as a +10 bonus to "uncontested" Perception checks to see things, but I think you've got the right of it for applying it as a penalty to stealth.

On this basis, perhaps the Size Modifier should be inverted and applied as a bonus to stealth?

A cat (SM -4) has a much easier time sneaking past someone in a hallway (normally -5) than a child (SM -1) or an adult (SM 0). My cat actually did it last night, which is why I think of this example :) Or for another example, a mouse can hide in a forest clearing - even if there's no grass to give it cover, just a flat bed of moss, the mouse has a significant advantage over me for hiding "in plain sight".

I might not assess the full -10 unless there's a distinct colour contrast - a brown or black mouse hiding in an empty white room is much worse off than a brown or black mouse hiding in an empty room with a brown carpet.
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Old 02-29-2012, 11:32 AM   #10
Anthony
 
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Default Re: Stealth -- does it use JUST MoS or do range penalties apply?

My usual interpretation of stealth is that stealth is a simple contest at the range where you normally figure a person might be able to hide, without addressing what that range is, since it's going to vary quite a lot with the situation, but in practice it's GM-able enough.
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