Does Smoke Block Line of Sight?

[DRD1812]

Do smoke grenades block line of sight? My group is coming out of Pathfinder 1e, so we're mostly thinking of fog cloud, which is how we wound up ruling it at the table (can't use sight to locate a target further than 5' through the smoke). Here are the relevant rules:

SMOKE GRENADE
A smoke grenade deals no damage; instead, it releases a cloud of dense smoke. Each character who inhales smoke must succeed at a Fortitude saving throw each round (DC = 15 + 1 per previous check) or spend that round choking and coughing; he can do nothing else. A character who chokes for 2 consecutive rounds takes 1d6 nonlethal damage. (Active environmental protection from a suit of armor prevents this effect altogether.) Regardless of the armor a character wears, smoke obscures vision, granting concealment to anyone within it.

LINE OF SIGHT
Line of sight is a straight, unblocked path that indicates what you can see. Line of sight is like line of effect, except factors that limit normal vision, such as fog, darkness, and total concealment, can block line of sight. If you can’t see a target for any reason, you do not have line of sight to it, and thus you cannot use effects that require you to have line of sight. You cannot have line of sight that exceeds planetary range unless otherwise indicated.

[Pantshandshake]

Line of Effect
Source Starfinder Core Rulebook pg. 271
If a weapon, spell, ability, or item requires an attack roll and has a range measured in feet, it normally requires that you (or whoever or whatever is using the ability) have a line of effect to the target to be effective (subject to GM discretion). A line of effect is a straight, unblocked path that indicates what an attack or ability can affect. A line of effect is blocked by a solid barrier that can stop the effect in question (such as a wall, for most effects), but it is not blocked by purely visual restrictions (such as smoke or darkness). You cannot have line of effect that exceeds planetary range, unless otherwise indicated.

So, you'd have line of effect to a target inside smoke, you just need to deal with various levels of concealment, and possibly cover if laser weapons are afoot.

This sounds right to me, though I'm not 100% confident I'm correct.

[Cellion]

Effects don't do anything that they don't say they do. A smoke grenade obscures vision and grants concealment but not total concealment. Therefore it doesn't block line of sight.

[BigNorseWolf]

Cellion wrote:

Effects don't do anything that they don't say they do. A smoke grenade obscures vision and grants concealment but not total concealment. Therefore it doesn't block line of sight.

A smoke grenade deals no damage; instead, it releases a cloud of dense smoke. Each character who inhales smoke must succeed at a Fortitude saving throw each round (DC = 15 + 1 per previous check) or spend that round choking and coughing; he can do nothing else. A character who chokes for 2 consecutive rounds takes 1d6 nonlethal damage. (Active environmental protection from a suit of armor prevents this effect altogether.) Regardless of the armor a character wears, smoke obscures vision, granting concealment to anyone within it.

Huh.. thought they blocked los apparently not though

[HammerJack]

You may have been thinking of Fog Cloud, which does still block LoS past 5 ft, in Starfinder. I have wondered, myself, if smoke grenades were intended to have similar effect, but I think the smoke may be deliberately thin enough to only offer concealment, so that a Kalo Commando Squad doesn't become quite as unstoppable as easily.

[Metaphysician]

Though there is no reason you couldn't have a Smoke Grenade Mk 2/Enhanced or whatnot, whose main change is that it provided Total Concealment rather than simply Concealment.

[ZeroShifter]

The rules text for smoke grenades seems to assume that all creatures use visual senses when it says "smoke obscures vision, granting concealment to anyone within it."

Nonvisual senses should be considered, as HammerJack implied. For example, a khizar has blindsight (life). A smoke grenade would not prevent a khizar from perceiving or attacking a living creature, as blindsight is a precise nonvisual sense.

I know it makes smoke grenades useless against a variety of creatures, but it falls in line with blindsight senses being "precise like vision but creatures can use them without needing to see". They appear to be the exception to the smoke grenade/line of sight question.

[HammerJack]

Not useless. Smoke inhalation is really harsh.

[ZeroShifter]

You're right. I was thinking purely in terms of vision.

[Metaphysician]

That would hardly make smoke grenades useless, it just would mean that "this device that produces visual obstruction does not help in situations where visual obstruction doesn't matter". I imagine that there are probably equivalents to smoke grenades targeting other common forms of precise senses, at least on planets or in star systems where people with such senses are common.

[gnoams]

So I just dropped a smoke grenade in a sfs mod, and we were looking closer at the wording and it appears to be rather borked.

"smoke obscures vision, granting concealment to anyone within it." So as written two people, standing on opposite sides of the cloud, have no concealment shooting at one another through the cloud, because neither of them are in the cloud. If one of them steps forward into the cloud then he gets concealment, but still doesn't have concealment shooting against the guy not in the cloud. Only if they are both in the smoke do they both gain concealment. That just makes no sense.

[BigNorseWolf]

gnoams wrote:

So I just dropped a smoke grenade in a sfs mod, and we were looking closer at the wording and it appears to be rather borked.

"smoke obscures vision, granting concealment to anyone within it." So as written two people, standing on opposite sides of the cloud, have no concealment shooting at one another through the cloud, because neither of them are in the cloud. If one of them steps forward into the cloud then he gets concealment, but still doesn't have concealment shooting against the guy not in the cloud. Only if they are both in the smoke do they both gain concealment. That just makes no sense.

Thats not how obscurement works. If your line of fire from Space Bob to Space Jim passes through a square that provides concealment then they have concealment. This is why the rules are nested, so they don't need to be repeated for every item using them.

Originating from sources such as dense smoke and battlefield position, concealment obscures precise senses and imposes a miss chance on attacks......

To determine whether you have concealment from a creature’s ranged attack, choose a corner of the enemy’s square. If any line from this corner to any corner of your square passes through a square that provides concealment or the border of such a square, you have concealment. Also use these rules when a creature makes a melee attack against a target that isn’t adjacent to it.

p 253

[Hawk Kriegsman]

The smoke grenade as written in the rules is really more of a tear gas grenade.

Military grade smoke grenades really don't hamper your breathing (well, ok if you are standing right next to it and huffing the smoke).

The absolutely block line of sight when looking into it or through.

So in my game all smoke grenades do is block LOS and grant total concealment.

Smoke grenades per RAW are called now called tear gas grenades and function as written.

[gnoams]

Another thing we ran into with the smoke grenade: I shot a line weapon through the smoke. We looked and couldn't find anything that said aoe attacks ignore concealment, so I rolled a miss chance for it.

[Garretmander]

gnoams wrote:

Another thing we ran into with the smoke grenade: I shot a line weapon through the smoke. We looked and couldn't find anything that said aoe attacks ignore concealment, so I rolled a miss chance for it.

Seems to me to be as intended. A line weapon depends on an attack roll. If the targets have concealment, that applies to said attack roll, for each target.

Seems pretty open and shut to me.

[Name Violation]

Fog, smoke, and other clouds provide both cover and concealment from laser attacks. Lasers can penetrate darkness, but they don’t provide any illumination.

[HammerJack]

Regarding the line weapon, yes it's correct that there isn't a blanket rule stating that AoE ignores concealment, because there are a lot if variations. If a Blast weapon had been used, instead, then concealment wouldn't matter, because ignoring concealment is part of the Blast property.