How do vision penalties due to darkness work?

Question

So, the penalties that are applied when two characters are in darkness, attacking each other, are perfectly clear in the Pathfinder rules:

In an area of dim light, a character can see somewhat. Creatures within this area have concealment (20% miss chance in combat) from those without darkvision or the ability to see in darkness.

In areas of darkness, creatures without darkvision are effectively blinded. In addition to the obvious effects, a blinded creature has a 50% miss chance in combat (all opponents have total concealment), loses any Dexterity bonus to AC, takes a –2 penalty to AC, and takes a –4 penalty on Perception checks that rely on sight and most Strength- and Dexterity-based skill checks.

Clearly, two enemies in the same light level are going to have a miss chance and possibly no dex bonus and a penalty to AC.

Where the problem comes in is when there are two enemies in different light levels attacking eachother. In the following situations, who gets what penalty?

Xylitol, a wizard in bright light, is firing a scorching ray at Aspartame, a wizard in dim light. Aspartame fires a scorching ray back at Xylitol. By RAW, which wizard(s) get a 20% miss chance?

Aspartame casts deeper darkness, placing himself in darkness. Xylitol and Aspartame fire more scorching rays at each other. By RAW, which wizard(s) have a 50% miss chance, and which one(s) lose their Dex bonus to AC, take -2 to AC, and -4 to Perception checks?

Answer 1

In uniform, shared light levels, vision penalties due to darkness work fine, intuitively, and exactly as written (no surprises). The deeper the darkness, the more trouble you have seeing, hitting things, and protecting yourself.

This, however, isn't the case you're asking about.

Mixed lighting conditions

Let's stick with RAW to analyse this situation of two people in different lighting conditions. The results are almost entirely the same whether whether Aspartame is in magical darkness or the (possibly very dark) shadow of an oak tree. The results are going to be weird.

• While Aspartame is in dim light, he has concealment.
  • Xylitol gets a 20% miss chance firing upon Aspartame, because Aspartame has concealment.
  • Aspartame can't see clearly, because he's in dim light. (Even though Xylitol is standing right there in bright light.) He either fires upon Xylitol without difficulty, or suffers the same 20% miss chance for firing through squares that grant concealment.

• While Aspartame is in darkness, he is blinded.

  • Xylitol has a 20% miss chance still, if we interpret Aspartame as still having dim light concealment. Natural darkness doesn't provide concealmnet explicitly, just blinds people in it.

    • People in the Darkness spell's darkness, however, get total concealment according to that spell. Since Aspartame has total concealment, Xylitol has a 50% miss chance. (This is the only difference made by the spell. Aspartame is still blinded either way, because it is dark.)
  • Aspartame, who is standing in darkness, can't see anything and has a 50% miss chance firing on Xylitol who's in daylight.
  • Aspartame takes all the AC and sensory penalties for dealing with anything because standing in darkness has made him blind.

These results are pretty counter-intuitive. In real life, the rogue sneaking through the shadows has an advantage on everyone else, and you've probably handled it as such — the rogue themselves isn't blinded by being in the shadows, but they are in Pathfinder!

Pathfinder's vision penalties are counter-intuitive and weird because they don't correctly model vision as we know it: they give you trouble depending on the light level you're standing in, instead of giving you trouble based on the light level of the thing you're looking at. In reality I don't have trouble reading things in the dark because I'm in the dark, I have trouble because those things are.

Like I said though, they work fine when people are sharing the same light levels. They just weren't written with differing lighting conditions in mind and don't handle them well. The sacred RAW should be burned in this case upon the altar of This Could Have Been Written Better For These Cases. Rules are worth the results they produce, and here the results they produce are kinda dumb. Those who wish to apply it exactly because those are the rules can go ahead and suffer the headaches.

Drawing sense out of the ashes.

Pathfinder should probably just be modelling how things really work: darkness affects you based on what you're looking at, not what light level you're in. Accordingly, I'm making a recommendation that in mixed light levels, the RAW be interpreted for what it was probably intended to do — which just requires a small adjustment of the original RAW:

• Dim light: Being in dim light doesn't make you have trouble seeing, but looking at things that are in dim light means you have trouble seeing those things. Past that though the RAW works fine: things in dim light have concealment and you have a 20% miss chance against them.
• Darkness: Being in darkness doesn't make you blind or suffer penalties. However, you are considered blinded for the purposes of observing or interacting with anything that is in the dark. You have a 50% miss chance against those things in combat, you have penalties to AC and perception versus things in darkness, and so on.
  • Alternately, stick with the Darkness spell's function, and just grant things in darkness total concealment and forget about blindness.

Wyrmwood brings up in comments that due to firing through concealment, firing past/through dim light introduces a 20% miss chance. This causes sense-making problems if you're on a long archery range, and a tall tree off to the side is casting a shadow across part of the middle of the range: those rules assert your target dummy now has concealment, despite still being in the bright daylight. These rules work fine for actual obstructions like black smoke, but not for light. I suggest that for the purposes of firing through concealment, don't count dim or dark squares — just count what it is you're targeting.

That produces these results, which are probably actually intuitive:

• While Aspartame is in dim light:
  • Aspartame is considered as having concealment from Xylitol. Xylitol has trouble seeing him, and has a 20% miss chance.
  • Aspartame fires without difficulty, because Xylitol is in bright daylight and clearly visible.
• When Aspartame is in darkness:
  • Xylitol is considered as being blinded for the purposes of trying to observe Aspartame. He has a 50% miss chance trying to attack Aspartame.
  • Aspartame still fires without difficulty, because Xylitol is in bright daylight and clearly visible.
  • Xylitol has all the defensive and sensory penalties for the purposes of any interaction between himself and Aspartame, because he can't see what Aspartame is doing at all.

We get these results, again, whether the dim light or darkness is due to magic or the shade of an oak tree.

Answer 2

By RAW in the area you quoted, characters gain concealment when in dim light, but seem to gain blindness when in darkness while not affecting those attacking them. The important clause for dim light is this:

Creatures within this area have concealment (20% miss chance in combat) from those without darkvision or the ability to see in darkness.

While the important clause for darkness is this:

In areas of darkness, creatures without darkvision are effectively blinded.

Clearly we have some asymmetry. At this point, it seems that dim light provides a defensive boon to those within it, and darkness gives no defensive bonus to those standing in it -- instead, it blinds them. This doesn't seem to make much sense.

We gain some insight from the combat chapter of the book. There isn't much that explicitly spells out an answer to your question, but under the section labeled "Concealment" we see something telling:

Ignoring Concealment: Concealment isn't always effective. An area of dim lighting or darkness doesn't provide any concealment against an opponent with darkvision.

This implies that an area of dim lighting or darkness does provide concealment against an opponent without darkvision. So the question is, how much concealment? The description of the darkness spell helps us out here:

All creatures gain total concealment (50% miss chance) in darkness.

So finally, we can conclude the following:

• Dim light provides all creatures standing within it with concealment (20% miss chance).
• Darkness provides all creatures standing within total concealment (50% miss chance), and also incurs blindness on any creature that does not have darkvision.

So, with all this in mind, let's look at your examples:

Xylitol, a wizard in bright light, is firing a scorching ray at Aspartame, a wizard in dim light. Aspartame fires a scorching ray back at Xylitol. By RAW, which wizard(s) get a 20% miss chance?

Aspartame is in dim light, so he has concealment against creatures without darkvision or the ability to see in darkness. Xylitol has a 20% chance to miss Aspartame. Aspartame suffers no penalty in his attempt to hit Xylitol.

Aspartame casts deeper darkness, placing himself in darkness. Xylitol and Aspartame fire more scorching rays at each other.

Aspartame is in darkness, so he is both blind and has total concealment.

Since Aspartame is blind, he gets a 50% chance to miss anyone he tries to attack, loses his Dexterity bonus to AC, takes -2 to his AC, and takes -4 to Perception checks. He has a 50% chance of missing Xylitol.

Since Aspertame has total concealment from being in Darknesss, Xylitol has a 50% chance to miss Aspertame. Xylitol is not in darkness and is therefore not blind and does not suffer from any of the penalties blindness incurs (losing Dex bonus, -2 to AC, and -4 to perception checks).

Answer 3

RAW doesn't seem to have any more to say about it than what you have quoted, thus leaving it up to DM discretion.

Xylitol, a wizard in bright light, is firing a scorching ray at Aspartame, a wizard in dim light. Aspartame fires a scorching ray back at Xylitol.

Aspartame is concealed and Xylitol is not.

Aspartame casts deeper darkness, placing himself in darkness. Xylitol and Aspartame fire more scorching rays at each other.

In this case, neither can see the other. Both have total concealment from each other. Aspartame will take all penalties, as he is in darkness. Xylitol can still see the ray coming once it leaves the darkness area, so doesn't take the other penalties.

Answer 4

the RAW rules are simply stupid when considering NATURAL darkness. clearly it should be possible to see things close to a light source, even if you are too far away from the light to be illuminated yourself. so you should not get a miss chance or perception malus for targets inside of the illuminated area, even if you are in darkness. and anyone trying to see or hit a target in darkness should get the miss chance and perception malus. that seems like the most logical way of doing it, when trying to emulate real life. and i would argue the same thing for AC. the person in the light cant see the person in the dark, so she wont know if and when the person in the darkness attacks, which makes it much harder to dodge. however the person in darkness can clearly see when the person in the light will start the attack, so she should be able to react. the other rules for concealment from ranged attacks also dont make much sense. because they would grant you concealment, whenever there is a concealed field between you and the attacker (this would include spots of dim light and darkness). one can easily see that this doesnt make much sense for natural types of dim light or darkness (for the same reasons as above).

however it is quite a different story if you look at magical darkness. because magical darkness is not just the absence of a light source. in this case light is actively blocked from moving through an area, so it should actually work like smoke or fog (in these cases the light is blocked by small particles, not magic). so anything that is inside or behind a magical dark spot from your point of view would seem dark (or dim respectively). especially anyone inside of the darkness would see everything else as dark (even things in an illuminated area, because the reflected light that would usually enable you to see illuminated objects is also blocked). so i would say, in the case of magical darkness, both sides get the mali, if either one is inside of a dark field or there is a dark field blocking the line of sight. i think this makes sense, if you compare it to how smoke/fog works in real life. one could also argue, that you dont get any darkness mali if you are right at the edge of a magical darkness area and looking out.