## Reciprocity of heavily obscurement.

8 posts / 0 new
Vernochan
Joined Dec 2010
3 Posts
I'm quite a bit confused about the rules regarding Obscurement, especially obsecurement.

The rules state clearly what happens if you are attacking a target in an obscured square.
But what happens when a target in such a square attacks?

Folling situation:
Someone is tanding in a large area of thick fog (Heavily Obscured)
Would a target outside the fog have concealmen, as there are several heavily obscured Squres between them.
What about when there are both standing of opposite sides of the fog? They are not standing in a heavily obscured square, but between them would be heavily obscured squares, logically hinderen LOS.

Awesome Ascii art:

Situation a:
t is the target, a the attacker

..........ffffffffff
..........ffffffffff
...t......ffffaffff
..........ffffffffff
..........ffffffffff

Situation b:
t is the target, a the attacker
..........ffffffffff..........
..........ffffffffff..........
...t......ffffffffff....o....
..........ffffffffff..........
..........ffffffffff..........
DevoDog
Joined Jun 2008
685 Posts

The rules state clearly what happens if you are attacking a target in an obscured square.
But what happens when a target in such a square attacks?

If the person being attacked is NOT in a square that has concealment, then they do NOT have concealment.  Intervening squares that are obscured have NO effect.
RisingZan
Joined Aug 2003
917 Posts

The rules state clearly what happens if you are attacking a target in an obscured square.
But what happens when a target in such a square attacks?

If the person being attacked is NOT in a square that has concealment, then they do NOT have concealment.  Intervening squares that are obscured have NO effect.

I strongly dispute the argument that intervening squares can have no effect.  The square the attacker is in has no effect, but intervening squares can have an effect.

Rules compendium, take your pick of pages 99, 106 or 313 on Line of Sight. The following is verbatim from RC 106-107 (emphasis mine)

"The user can see the target if at least one line doesn't pass through or touch an object or an effect - such as a stone wall, a thick curtain or a cloud of fog that blocks the user's vision

Even if the power's user can see a target, objects and effects can still partially block its view. If the user can see a target but at least one line passes through an obstruction, the target has cover (page 219) or concealment (page 220)."

An obstruction does not have to be a solid object - anything that hinders or interferes is by definition an obstruction, and a cloud of fog or dense foliage can certainly block, hinder and interfere with vision.

In both of the sample drawings above, all lines from the attacker to the target pass through an effect that causes squares to be heavily obscured, therefore both creatures have total concealment against each other.
The only effect where intervening squares don't matter is lack of light (dim light or non-magical darkness), because nothing is actually hindering vision in those squares, they just aren't illuminated.

The rules dispute seems to be that while the Line of Sight rules discuss effects in intervening squares, the definitions of Concealment and Total Concealment, Lightly Obscured and Heavily Obscured do not, and seem to indicate that only creatures in those particular squares can get concealment.   I feel this is due to sloppiness on the part of the writers and not because they actually intended intervening squares to have no effect.  The LoS rules are clear that the intervening squares do apply, even if they concealment and obscurement rules leave that discussion out.

Mand12
Joined Jun 2010
17444 Posts
Yeah, the "intervening obscurations don't count" argument is fundamentally flawed.  Yes, the definition of obscured squares doesn't grant concealment reciprocally, but that's not the only rule governing the situation.

Given that "cloud of fog" is explicitly mentioned as something that can block vision and cause concealment, the argument that "obstruction" means blocking terrain is also invalid.
D&D Next = D&D: Quantum Edition
mvincent
Joined Jun 2004
8513 Posts
Intervening squares that are obscured have NO effect.

Yes they do. You might be thinking of intervening illumination (which is a bit different that other obscuring effects). The illumination level in your target's location is what matters. PHB p.262 "Creatures in the area have concealment" "can’t see creatures or objects in darkness". This does not conflict with PHB p.273: "You can see the target if at least one line doesn’t pass through or touch an object or an effect—such as a wall, a thick curtain, or a cloud of fog—that blocks your vision", since a non-illuminated area would not "block your vision" to an illuminated area on the other side of it.

DevoDog
Joined Jun 2008
685 Posts
Zan,
I stand corrected. I was basing my answer only on the OP's post.
Your last paragraph is valid (the cause of the problem and probably what the intent was).

Unfortunately, I doubt we'll ever get a final answer on this one.
RisingZan
Joined Aug 2003
917 Posts
Zan,
I stand corrected. I was basing my answer only on the OP's post.
Your last paragraph is valid (the cause of the problem and probably what the intent was).

Unfortunately, I doubt we'll ever get a final answer on this one.

You're not the only person on these boards or to play the game to argue it that way.  I know Alcestis made the same arguement in the simple question thread about a week ago, but didn't respond again when I made the argument I made above.
It's one of those rules where if you only look at a limited portion of the rules it reads one way, but once you look at other rules, its read another way.

Luckily its one of those areas where once you take all the applicable rules into account, the actual behavior of the rules and the common sense expectation based on real world analogues are one and the same.
DevoDog
Joined Jun 2008
685 Posts
I also wasn't looking at the OPs diagrams either.  So, it wasn't that I was "wrong" per se....I just wasn't answering the actual question being asked.