Guide to Range and LOS

By Zaltyre, in Descent: Journeys in the Dark

After many questions and discussions about these concepts, I'm happy to announce that I've put together a tutorial document for range and line of sight in Descent. I hope this will be helpful for new players as well as for journeying veterans with questions. It gives step-by-step instructions for counting spaces and tracing LOS, and also explains some of the fringe cases of each process.


All of the information in the guide represents the RAW as best I understand them. While LOS in particular has many house rules floating around, I think knowing the RAW is an important step to deciding whether or not to implement house rules, and for determining how abilities are intended to work.


You'll notice that this is version 1. If you've got questions, comments, or feedback, please let me know. Thanks!



Edited by Zaltyre

A great document. Really helpful, both for newcomers and for experienced players. And a wonderful reference for any discussions!

I have only one suggestion: In the section where you explain the LOS in the presence of 'thin walls' (Diagram 14 and 16) you might want to introduce this term. (This might also be a term for your glossary)

I know the term 'thin walls' is not part of the RAW, but since this is a case which is often house-ruled and is probably giving most new players a bit of a headache, it might be helpful to introduce this term (as a technical term).

This way, it would be very simple to search for this term in your document(s) and point new players to certain issues more easily.

Thanks for the suggestion, Chaoticus. I agree "short segment of a map edge" is a little clunky as far as wording. For the glossary I've tried as much as I can to stick to the words and phrases found on cards and in the rulebook, but this might be a good spot to make an exception.

ok i read the doc with a nice beer at my side.
And everything was going right.
Mmh..Yeah, ...of course...that s it... Naturally...
And then came that Bloody diagram with the Ettin :) ...and i choke on my beer.
I realized that we may have more or less shortcut the rules for 4 years by permitting the Ettin to attack in that situation.

By the way i have a question about LoS regarding pits.
I agree that a figure in a pit has only LoS on an adjacent figure.
But for a figure out of a pit space it is only said that you have to be adjacent to a pit (not particularly the space within the other figure is) to have LoS
to the figure that is in the pit.
So my interpretation was that in your diagram the 4 spaces figure has LoS to the figure in the pit even if they are not directly adjacent.
It was for me more or less an exception to the reversibility of LoS.

Hi Paul,

great work, thank you !

A question about Diagram 8 - Ettin can not attack:
Where does the rules say that you have to "shrink" a large monster to a single space while attacking ? Do range and LOS have to start both from the same space ? For the rules the attacker is a "figure" with a target "space".

The ettin figure has LOS and always range 2 - a valid attack in my opinion.

Diagram 8 has been the most commented on part of the guide already. I'm going to submit the question to FFG just to double-check myself. However, I think most of the confusion is arising because I wrote the description of that diagram sort of backwards.

If you look at Diagram 8 from the hero's perspective (not from the Ettin's) the point about measuring range to the target space is much more clear. That is, the hero is 2 spaces away from the Ettin (counting over the obstacle) but his only valid target space is the bottom right corner of the Ettin. When attacking, you've got to measure range to the target space. The range to that space (from the hero) is 3.

There are a few possibilities here:

1) I'm right. The ettin can't attack the hero, and the hero can't attack the ettin. The target space is always 3 spaces away from the space LOS is being measured from , so it is too far for reach.

2) I'm wrong. The hero can't attack the ettin, but the ettin CAN attack the hero. He's measuring "to the target space" in both cases, just from different spaces of his.

3) I'm really wrong. They can each attack each other, because the "2 spaces away" and "LOS" requirements are separate.

Thank you for pointing this out. I'll post the answer here (and in the comment section of my document if things need to change in the next version) when I get it.

Edited by Zaltyre

I understand that you're simply clarifying the RAW, but the ruling on diagram 16 (standing on opposite sides of a thin wall) is really nonsensical and actually is in direct contradiction with the inherent geometry of how LOS works in D2e. In the RAW, only the 1st instance does not have LOS. But in physical actuality, all the instances you showed should not have LOS.

The way I see it, thin walls are objects of confusion because they're1-dimensional objects forced to exist in a 2D space. But since there's no such thing as 1D objects (i.e. comprising of only length, without width) in the physical reality of a 2D world (the board), you have to give those thin walls a "virtual thickness". That is, pretend it's a skinny rectangle rather than an idealized line.

But as soon as you realize that it's not a line, but just a skinny rectangle... you can see how all of those instances in diagram 16 would have the LOS line running along the edge of the wall, and therefore all of them do not have LOS.

As someone with an interest in physics, that's the only explanation I can accept.

As someone with an interest in physics, that's the only explanation I can accept.

Believe me when I say I have been down that road. For quite awhile, every group I've played with has treated the end of the map edge not as a corner (as most of Diagram 16 demonstrates) but as a very short edge (like you say).

What I can tell you is that if you want the LOS rules to be both realistic and logically consistent, you're going to be disapointed.

When I played with the houserules, I approached it in the most logical way I could- projections (dot products). If you project into a 1D space, you can see that indeed, there is no realistic way A can see B in the 4 left panels of Diagram 16. The problem is when you take that approach, you realize that (physically) the right panel of 16, of 14, and all of 13 shouldn't have LOS either. Essentially, the entire concept of "corner vs edge" goes out the window (which is not unexpected, as a point is just an infinitely short line segment).

In order to maintain any semblence to the current system, you MUST be a little lax with realism. In our simplified picture, the top left diagram WOULD have LOS because the separation is a corner, not an edge. However, a specific exception makes those two spaces nonadjacent, and have no LOS.

My goal with this guide is not to make you like the D2E system. It is to explain clearly what that system is. Like the Bohr model of the atom, Descent LOS is not correct, but it is correct enough in enough aspects that it is a workable (and so much more importantly, simple) model.

I just uploaded version 2 to the file section (link in signature), it should post within the next few days. Diagram 8 (the ettin) has been corrected to reflect the FFG rules response, and a few other sections have received improvements to make them more understandable.

Zaltyr I'm a new player guiding a new group with the game(have played one game so far with many errors).

I am so glad I found this post. I have been reading it several times so I don't make mistakes the next time I play. I really want to play with the raw rules before I decide anything else and your guide is super super helpful.

I would be really glad if you could add a move ruling clarification section also(won't be as long)

My current concern is that I have seen conflicting answers as to movement diagonally when a black edge is covering a bit of the corner to make the 2 tiles seem non adjacent.

In your guide they are considered non adjacent and there is no los but on numerous other posts I saw people saying that movement is allowed citing the raw rules.

Thanks a lot and have a nice week

Edit:

I just saw the new version! Great work! So just as to use the same wording I meant movement along map border segment (if I understand this correctly)

Edited by SatanShiro

That map border segment is legitimately a little weird. The best way I can say to approach it from a LOS perspective is to treat the end of it like a corner, not like an edge. The case where two figures are right up against it is an exception, not the rule (hopefully Diagram 16 covers that).

Anyway, regarding movement, it's clear from the rulebook that the two spaces on opposite sides of that segment are not adjacent, and this means you cannot move directly from one to the other. To be as clear as I can be, in the picture below space A is adjacent to the blue spaces shown (top diagram) and B is adjacent to the blue spaces shown (bottom diagram). A figure in space A could move to either of the blue spaces regardless of whether or not the one directly above A is blocked. Likewise, a figure in B could move to any of the blue spaces regardless of which other ones are blocked. A figure would not be able to move directly from A to B, as they are not adjacent spaces. It would require moving 2 spaces to get from A to B, because the range from A to B is 2.

NgHRbiG.jpg

Hey

Thanks so much for your reply

I was somewhat sure that if the black line extends a bit it means that the diagonal movement is forbidden for A(as he does not share the corner anymore.

I was watching critplays on YouTube and was sure that's what he said in one of his videos but now I can't find it again so I guess I was wrong.

I'll look at it again later just to be sure as it does look on some tiles that black lines extend a bit to cover a specific edge on purpose.

Thanks in advance and sorry for the long post have a nice day

That "little bit of overhang" is just artwork. It does not prevent diagonal movement/ sight any more than a corner would.

Hello Guys,

Yesterday we ran into a wired counter-intuitive wall-related LOS question I wanted to post for confirmation.

Consider the following situation (peasant marker = hero) . Without the minion Ettin, it is clear that hero and master Ettin have LOS to each other. However, does the situation change as soon as the minion Ettin is placed? I dare say no from everything I know about LOS. This is nevertheless the most counter-intuitive situation I can imagine. What do you guys say?

5963c4028cb14_Screenshot2017-07-1020_00_03.jpg.94fe5315c611de721c214102ed2f34d4.jpg

9 minutes ago, Chaoticus said:

Hello Guys,

Yesterday we ran into a wired counter-intuitive wall-related LOS question I wanted to post for confirmation.

Consider the following situation (peasant marker = hero) . Without the minion Ettin, it is clear that hero and master Ettin have LOS to each other. However, does the situation change as soon as the minion Ettin is placed? I dare say no from everything I know about LOS. This is nevertheless the most counter-intuitive situation I can imagine. What do you guys say

As counterintuitive as it might be, you are correct. In this scenario the master Ettin retains line of sight, regardless of the presence of the minion Ettin.

I play with the Imperial Assault Line of Sight rules in Descent myself.. but even with those rules, the hero remains in line of sight :P

Goes to show line of sight is a hard problem to nail down!

Edited by Charmy

Hey Zaltyre, thinking about this line from your guide “Adjacent” means a range of exactly 1."

Do you play it that you need range of (1+3) 4 to hit a Stealthy target? And 5 with reach?

That would be so cool if this was officially confirmed, I'd love my Deep Elf even more but I think they already said the 3+ will do to hit with melee right?

I am not Zaltyre, but I guess he won't mind me to ninja this.

For Melee attacks (even for those with reach) no range is required. It has been confirmed by FFG that melee attacks on Stealthy targets need range 3 (0+3). ( Source )
For Ranged attacks on adjacent targets a range of 1 is required. Thus, Ranged attacks on adjacent Stealthy targets need a range of 4 (1+3)

Edited by Sadgit

Thanks, Sadgit.

Alarin, my purpose in saying "exactly 1" was to stress that range 0 is not adjacent, range 2 is not adjacent. Range 1 and only range 1 is considered to be adjacent. Note that while stealthy alters the range an attack requires to hit, it does not alter the actual range between the spaces.

ook, thank you both! :)... I was just wondering how do you guys play it