line of sight versus cover

13 posts / 0 new
Last post
I'm playing a cunning sneak rogue and am trying to better understand line of sight versus cover. Are the two mutually exclusive?

If they are not, then how can a cunning sneak hide from a monster with only partial cover or concealment since the monster will have line of sight and be able to see the hidden rogue?

Similar question regarding the Armor of Dark Deeds + Cunning Sneak combo I hope to use. I gain concealment w/ the armor and can theoretically hide as a cunning sneak, but monsters will still have line of sight on me, ending the hiding?
Sticky, top of the forum, "Rules of the Hidden Club." Read it and you should understand everything about 4e's stealth rules.
I'm playing a cunning sneak rogue and am trying to better understand line of sight versus cover. Are the two mutually exclusive?

If they are not, then how can a cunning sneak hide from a monster with only partial cover or concealment since the monster will have line of sight and be able to see the hidden rogue?

Similar question regarding the Armor of Dark Deeds + Cunning Sneak combo I hope to use. I gain concealment w/ the armor and can theoretically hide as a cunning sneak, but monsters will still have line of sight on me, ending the hiding?

Line of sight and cover are not mutually exclusive: it's possible for creature A to have line of sight to creature B even though B has cover against A.  For example, A and B are on opposite sides of a hard corner.  A more provocative example is where A and B are on opposite sides of a wall made of indestructible glass with an arrow slit in it: each creature can see the other perfectly well, but glass wall with arrow slit still provides superior cover.

Your second question isn't about what the rules are so much as about how realistic the rules are.  I guess here you can assume that adventurers and monsters are skilled at exploiting partial cover to remain hidden.  Again, if two creatures A and B are on opposite sides of a corner, and creature B was already hidden from A, it seems plausible that B can exploit the corner to remain hidden.

Line of sight won't end stealth.  To become hidden, you need superior cover, total concealment, or lack of line of sight, but to maintain it partial cover or partial concealment suffice.

Hope this helps. 
From the forum FAQ, if desired:
'What's the difference between cover and line of effect? Per the cover rules, “a line that runs parallel right along a wall isn’t blocked”. However, If every imaginary line you trace to a target passes through or touches a solid obstacle, you don’t have line of effect to the target”. So two medium opponents separated by a 5’ wide square column technically don't have superior cover against each other, even though line of effect is blocked.'
Thank you all for the help!
After thinking about this a bit more, I'm now convinced that the rules are unrealistic in allowing cover (in addition to concealment) to assist in becoming or remaining hidden.  Cover is supposed to be just physical barriers between two creatures, but the physical barrier can be perfectly transparent, such as a wall of glass.  And it's really weird that you can become or remain hidden just from being behind a wall of glass.

Concealment makes more sense, because concealment is stuff that prevents you from being seen.  (Or, more generally, detected?  Can smells provide concealment from your scent?)  So, it makes sense that you can become or remain hidden behind a thick fog, even though there's clear line of effect (no physical barrier).
The issue though is that the vast, vast majority of cover is also opaque, and that the system math  breaks down a bit if you allow the same effect (standing behind typical cover) to provide both cover and concealment, which do stack.

They want there to be a distinction between being behind an arrowslit and being behind an arrowslight in a fog, mechanically.  Granting cover the effect of the corresponding concealment makes cover too strong for attack rolls.

That this has a nonsensical application to transparent cover and the stealth rules is collateral damage, but much less severe than the impact on the attack mechanics.
D&D Next = D&D: Quantum Edition
So if my PC is hiding behind a table (cover) and there's smoke from fire (concealment) they don't stack ?  I get whichever is the bigger bonus instead ?
"Non nobis Domine Sed nomini tuo da gloriam" "I wish for death not because I want to die, but because I seek the war eternal"

IMAGE(http://www.nodiatis.com/pub/19.jpg)

the physical barrier can be perfectly transparent, such as a wall of glass.

Right, but that is a rare exception that I wouldn't expect to always be accounted for. (btw: thanks for the earlier message!)

The issue though is that the vast, vast majority of cover is also opaque, and that the system math  breaks down a bit if you allow the same effect (standing behind typical cover) to provide both cover and concealment, which do stack.

They want there to be a distinction between being behind an arrowslit and being behind an arrowslight in a fog, mechanically.  Granting cover the effect of the corresponding concealment makes cover too strong for attack rolls.

That this has a nonsensical application to transparent cover and the stealth rules is collateral damage, but much less severe than the impact on the attack mechanics.


Yup, this seems exactly right to me.  Thanks for the explanation.
the physical barrier can be perfectly transparent, such as a wall of glass.

Right, but that is a rare exception that I wouldn't expect to always be accounted for. (btw: thanks for the earlier message!)



Thank you for everything you've done on these fora!  (Just as one tiny example, I appreciated your recent link to the Dragon article on game transparency, but I didn't bother to thank you on the forum.)
So if my PC is hiding behind a table (cover) and there's smoke from fire (concealment) they don't stack ?  I get whichever is the bigger bonus instead ?


No, they stack.  The point of Mand12's post is that if being around a typical (non-transparent) corner provided both cover and concealment, that would be too severe a penalty, precisely because the penalties stack.
right ok, all is well
"Non nobis Domine Sed nomini tuo da gloriam" "I wish for death not because I want to die, but because I seek the war eternal"

IMAGE(http://www.nodiatis.com/pub/19.jpg)