Expanded Light and Vision

# Expanded Light and Vision
<br>

*for 5e*

Many activities that adventurers perform, such as noticing danger, searching for hidden things, casting spells, and hitting things, rely on sight. Darkness and dim light can prove obstacles to characters unused to navigating low-vision conditions.

This small expansion aims to make lighting conditions more interesting and accurate.

Because a character's vision is unique to that character, penalties are tracked per-character rather than per-environment.

### Why an Expansion?
So  many character races and monsters come with 5e's version of Darkvision baked in. This gives characters without it a disadvantage, instead of giving an advantage to those *with* it. 5e's Darkvision is equivalent to previous editions' Low-Light Vision, which allows a character to see in dim conditions as if it were normal lighting, and darkness as if it were dim conditions.

Seeing in darkness as if it were dim light makes sense in several cases, such as how elves' vision is described as being used to shadowy forests and twilight. However, there are several races and monsters where that feline-like description falls flat. Drow, deep gnomes, and even tritons have reason to see in true darkness normally, not "as if it were dim light."

For these reasons, an expanded Light and Vision section for those groups and DMs that wish to add a little more flavor seemed prudent.

### Obscuration
Due to lighting, cover, or other factors, a character may percieve an area to be Unobscured, Lightly Obscured, or Heavily Obscured. Obscuration related to illumination exists only in a creature's perception, though obscuration related to other factors may not.

***Unobscured.*** Most areas without an obscuration detailed are Unobscured. Characters can see very well.

***Lightly Obscured.*** With some obstacles in the way, such as foliage, fog, or swarms of butterflies, a character may perceive an area to be Lightly Obscured. Sight-based ability checks such as Wisdom (Perception) and Intelligence (Investigation) are made at disadvantage, unless the character is not using sight.

***Heavily Obscured.*** When a sandstorm approaches, or characters descend deep underwater, a character may percieve an area to be Heavily Obscured. Sight-based ability checks such as Wisdom (Perception) and Intelligence (Investigation) automatically fail, unless the character is not using sight. Attack rolls a character perceiving Heavy Obscuration makes are made at a disadvantage. The DM may rule that attack rolls, too, automatically fail, if conditions specify.

A character perceiving Heavy Obscuration is Blinded, though the conditions of both overlap. Resolving the Blinded condition may nor remove the Heavy Obscuration, but removing the Heavy Obscuration removes the Blinded condition.

*Note:* The Blinded condition says that attack rolls against the creature are made with advantage. Heavy Obscuration disregards that specific effect, because it is focused on describing what the *character* may do, not what the conditions are like. At DM's ruling, and at the lack of an attacking creature's special ability, an attacking creature may gain advantage against a character perceiving an area as Heavily Obscured.*

### Illumination
The presence or absence of light creates four levels of illumination: Dazzling, Bright Light, Dim Light, and Darkness. Magical darkness effects are determined by the effect's description (such as the spell *Darkness.*) Illumination is a property of an area rather than a creature.

***Default Obscuration.*** This obscuration level is default for this illumination. Without Darkvision or similar effect, this does not change.

***Dazzling.*** This illumination level is equivalent to direct sunlight. Areas in direct sunlight are considered Dazzling, but do not impose any effects on most creatures. In extreme cases, such as direct sunlight reflecting on a field of snow or a glittering lake, the DM may rule that the Dazzling area is, in fact, Lightly Obscured for most characters.

***Bright Light.*** This illumination level is normal. If lighting conditions are not defined, Bright Light is assumed. This includes areas in indirect sunlight and most places indoors.

***Dim Light.*** This illumination level represents shadows, twilight, underwater, or other poorly-lit conditions. For creatures without Darkvision, conditions of Dim Light are Lightly Obscured for them.

***Darkness.*** This illumination level means that there is no light at all, such as underground, night, deep underwater, or in an unlit room. Most characters cannot see in darkness, and as such, the area is Heavily Obscured for them.

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### Vision
Every creature in the world has one of these vision traits. A vision trait may alter a creature's perceived obscuration in certain illuminations, it doesn't change the illumination itself.

For example, a tiefling and a human are both in an area of Dim Light. The tiefling, with Darkvision, perceives the Dim Light as Unobscured, and does not take penalties. The human, without Darkvision, perceives the same Dim Light as Lightly Obscured.

#### No Vision
A creature without vision, such as monsters without eyes or characters with little to no sight, perceives every type of illumination as Heavily Obscured. Any sight-based ability checks automatically fail, and sight-based attack rolls are made at disadvantage.

However, many creatures without vision are easily able to circumvent these penalties through training or intuition. It is assumed that characters with little to no sight do not rely on sight to make their usual ability checks or attack rolls, and so do not automatically fail or suffer from disadvantage, no matter the illumination level.

Having the No Vision trait does not preclude a character from having a Special Vision trait.

**Races with No Vision:** Any character may have No Vision.

#### Normal Vision
Normal vision does not change a creature's perceived obscuration level for the area's illumination level from the default.

**Races with Normal Vision:** aarakocra, centaur, changeling, dragonborn, firbolg, genasi, halfling, human, kenku, lizardfolk, satyr, warforged, et al.

#### Darkvision
This version of Darkvision remains unchanged from the usual rules. Creatures with Darkvision perceive Dim Light as Unobscured (or in other words, as Bright Light) and Darkness as Lightly Obscured, though without color.

Most creatures with Darkvision gain the benefits of it in a radius of 60' around them. Outside of this radius, illumination affects obscuration as if the creature had Normal Vision.

**Races with Darkvision:** aasimar, dwarf, elf, gnome, goblin, half-elf, half-orc, orc, shifter, tabaxi, tiefling, triton, et al.

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#### True Darkvision
Some creatures don't just see well in dim lighting, they see perfectly fine in conditions of true darkness, as well. To them, areas of Dim Light and Darkness are Unobscured. However, areas of Bright Light are Lightly Obscured, and Dazzling areas are Heavily Obscured. This represents their specially-adapted eyes.

Creatures with True Darkvision gain the benefits of it in a radius of 120' around them. Outside of this radius, illumination affects obscuration as if the creature had Darkvision up to the usual line-of-sight restrictions for Normal Vision.

True Darkvision is given to the races below and replaces both the Superior Darkvision and Sunlight Sensitivity traits.**

**Races with True Darkvision:** duergar, drow, svirfneblin (deep gnome), kuo-toa, et al.

#### Changing Your Vision
It is possible for a character's vision to change, abruptly or over time. Generally, without magical intervention, vision always proceeds down the scale: from True Darkvision to Darkvision to Normal Vision to No Vision.

If a character desires to change their vision over time, it is recommended that they use similar rules to the Training Downtime Activity found in *Xanathar's Guide to Everything.* Through exposing themselves to a certain lighting condition, A character does not require an instructor or gold to change their vision, but it takes ten weeks to change their vision one step, reduced by a number of weeks equal to their Constitution modifier (no penalty if negative.)

If a character's vision abruptly changes, such as an injury causing them to lose most of their vision, they lose their previous vision and gain the No Vision trait. They may or may not suffer from the effects of Heavy Obscuration for ten weeks, reduced by a number of weeks equal to their Constitution or Wisdom modifier, whichever is higher (no penalty if negative,) until they are accustomed to  their new vision trait.

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### Special Vision
Some creatures have Special Vision traits. These represent types of vision that expand upon regular Vision traits. Unless otherwise specified, Special Vision traits are permanent and constantly "on." These are optional traits that can be tacked onto an existing race or character, or perhaps granted through the use of spells and items.

If Special Vision traits are part of your game, consider allowing the spell *Darkvision* to be able to grant one of the Special Vision traits at a time.

#### Infravision
Seeing into the infrared spectrum allows characters to see traces of heat. In certain novels, it is a trait granted to the drow.

A character with Infravision may turn it on or off at will as a bonus action. While it is on, Dazzling and Bright Light conditions become Lightly Obscured to the character, if not already Lightly or Heavily Obscured. The character becomes able to see body heat and locations that are unusually cool or warm within a 60' radius. They have advantage on Wisdom (Survival), Wisdom (Perception), and Intelligence (Investigation) checks to track recent passings (generally defined as less than a day,) to look for a specific temperature, or to look for someone they suspect is using stealth.

Infravision does not allow a character to see magically-invisible creatures or items, and other illusions can fool it as well.

#### Ultravision
For the purposes of simplicity, seeing slightly into the ultraviolet spectrum allows characters with this trait to see things as if it were dark and a UV light were shining—that is, certain chemicals and light colors glow to that character. Many birds and insects can see into the ultraviolet spectrum, it may be a trait granted to aarakocra, kenku, and fairies.

A character with Ultravision may turn it on or off at will as a bonus action. While it is on, Dazzling and Bright Light conditions become Lightly Obscured to the character, if not already Lightly or Heavily Obscured. The character becomes able to see certain chemicals and residual magic effects within a 60' radius. They have advantage on Intelligence (Investigation) and Intelligence (Arcana) checks to find chemicals or determine the school of magic used in a spell no less than two hours old.

Ultravision does not allow a character to see magically-invisible creatures or items, and other illusions can fool it as well.

#### Blindsight
Many monsters with the No Vision trait also have Blindsight. This functions exactly the same as usual: creatures with Blindsight do not suffer any illumination-caused obscuration penalties within the radius specified, generally about 10'.

#### Truesight
Truesight is a trait granted to several monsters and characters at high levels. It allows a creature to see magically-invisible creatures, through illusions and shapechangers, see into magical darkness, and see into the Ethereal Plane.

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### What Do I Do With This?
Only a select few groups, characters, and games use lighting effects at all. This expansion is most useful to DMs who wish to use an extra environmental hazard, make Underdark races' vision make more sense, or for players who are thinking about using the No Vision trait for their character.

Using lighting descriptions can enhance players' mental images of a scene, such as describing the single lantern on the central table in a seedy bar, or the bonfires dotted through the small town's harvest festival. It can provide an extra layer of depth for those who want it, or you can just ignore it completely.

#### How to Determine Penalties
In a situation with lighting that differs from the norm, follow this flow to see what penalties a creature receives from a certain condition:

1. What is the illumination level?
2. What is the creature's vision?
3. How far away is the thing they're trying to see?
4. What is the obscuration level the creature is seeing through?
5. What penalties or benefits are a result of that obscuration level?

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> ##### *(Linked from Heavily Obscured)
> Because under the normal rules: if there are two creatures without Darkvision in Darkness and one makes an attack roll against the other, the advantage and disadvantage technically cancel each other out, and the attack roll is made normally. To get around that, you can say that Blinded doesn't affect non-PC creatures, but then we're just messing things up too much.

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> ##### **(Linked from True Darkvision)
> Replacing the traits Superior Sunlight Sensitivity with True Darkvision is a tradeoff, and I believe it is balanced and makes far more sense. 
> 
> A character with Superior Darkvision and Sunlight Sensitivity, the usual kind, has Light Obscuration penalties when in areas of darkness, and none in Bright Light and Dim Light, unless that Bright Light is specifically sunlight, which not much is (magically anyway.)
>
> A character with True Darkvision has no penalties in darkness and Dim Light, and increasing penalties for Bright Light and Dazzling, without the stipulation that the light has to be sunlight. This makes them more vulnerable to magical and mundane light, but also less reliant on bits of light to create the ideal Dim Light conditions.

##### Random Notes

"Bright light" should be the highest illumination level, but too many effects rely on the specific wording of "bright light" to bother changing it to "normal light" for a little document like this.

Same with "darkvision" and the slightly-better descriptor "low-light vision."

##### Author

/u/letteredviolet