These rules cover the various situations where objects and characters may or may not be noticed or targeted. # Cover A creature can benefit from cover only when an attack or other effect originates on the opposite side of the cover. If a target is behind multiple sources of cover, only the most protective degree of cover applies; the degrees aren't added together. | Degree | Benefit to Target | Offered By… | | -------------- | ------------------------------ | --------------------------------------------------------------------- | | Half | +2 to AC and DEX saving throws | Another creature or an object that covers at least half of the target | | Three-Quarters | +5 to AC and DEX saving throws | An object that covers at least three-quarters of the target | | Total | Can't be targeted directly | An object that covers the whole target | # Light The presence or absence of light determines the category of illumination in an area, as defined below. ### Bright Light Bright Light is normal illumination and lets most creatures see normally. Even gloomy days provide Bright Light, as do torches, lanterns, fires, and other sources of illumination within a specific radius. ### Dim Light Dim Light, also called shadows, creates a [[#Lightly Obscured]] area. An area of Dim Light is usually a boundary between Bright Light and surrounding Darkness. The soft light of twilight and dawn also counts as Dim Light. A full moon might bathe the land in Dim Light. ### Darkness Darkness creates a [[#Heavily Obscured]] area. Characters face Darkness outdoors at night (even most moonlit nights), within the confines of an unlit dungeon, or in an area of magical Darkness. # Obscurement Areas can be Lightly or Heavily Obscured, with consequences for gameplay. ### Lightly Obscured A Lightly Obscured area is an area with [[#Dim Light]], patchy fog, or moderate foliage. You have Disadvantage on Wisdom (Perception) checks that rely on sight. ### Heavily Obscured A Heavily Obscured area is an area with [[#Darkness]], heavy fog, or dense foliage. You have the [[Conditions#Blinded|Blinded]] condition when trying to see something there. # Hiding ![[Actions#Hide]] # Passive Perception Passive Perception is a score that reflects a creature's general awareness of its surroundings. The DM uses this score when determining whether a creature notices something without consciously making a Wisdom (Perception) check. A creature's Passive Perception equals 10 plus the creature's Wisdom (Perception) check bonus. If the creature has Advantage on such checks, increase the score by 5. If the creature has Disadvantage on them, decrease the score by 5. For example, a level 1 character with a Wisdom of 15 and proficiency in Perception has a Passive Perception of 14 (10 + 2 + 2). If that character has Advantage on Wisdom (Perception) checks, the score becomes 19. # Senses Characters and monsters can have special senses beyond normal vision and hearing. ### Blindsight If you have Blindsight, you can see within a specific range without relying on physical sight. Within that range, you can see anything that isn't behind [[#Cover|Total Cover]] even if you have the [[Conditions#Blinded|Blinded]] condition or are in [[#Darkness]]. Moreover, in that range, you can see something that has the [[Conditions#Invisible|Invisible]] condition. ### Darkvision If you have Darkvision, you can see in [[#Dim Light]] within a specified range as if it were [[#Bright Light]] and in [[#Darkness]] within that range as if it were Dim Light. You discern colours in that Darkness only as shades of gray. ### Tremorsense A creature with Tremorsense can pinpoint the location of creatures and moving objects within a certain range, provided that the creature with Tremorsense and anything it is detecting are both in contact with the same surface (such as the ground, a wall, or a ceiling) or the same liquid. Tremorsense can't detect creatures or objects in the air, and it doesn't count as a form of sight. ### Truesight If you have Truesight, your vision is enhanced within a specified range. Within that range, your vision pierces through the following: **Darkness.** You can see in normal and magical [[#Darkness]]. **Invisibility.** You see creatures and objects that have the [[Conditions#Invisible|Invisible]] condition. **Visual Illusions.** Visual illusions appear transparent to you, and you automatically succeed on saving throws against them. **Transformations.** You discern the true form of any creature or object you see that has been transformed by magic. **Ethereal Plane.** You see into the Ethereal Plane. # Perception and Encounters This section is taken from the _Dungeon Master's Guide_, page 36 \[[[D&D 5.5E DMG.pdf#page=40|link]]]. If the characters encounter another group of creatures and neither side is being stealthy, the two groups automatically notice each other once they are within sight or hearing range of one another. The **Audible Distance** table can help you determine the hearing range, and the following sections address visibility. If one group tries to [[Actions#Hide|hide]] from the other, use the rules in the _Player's Handbook_. **Audible Distance** | Noise | Distance | | ------------------ | ------------- | | Trying to be quiet | 2d6 × 5 feet | | Normal noise level | 2d6 × 10 feet | | Very loud | 2d6 × 50 feet | **_Visibility Outdoors._** When travelling outdoors, most characters can see about 2 miles in any direction on a clear day, except where obstructions block their view. That range increases to 40 miles if they are atop a mountain or a tall hill or are otherwise able to look down on the area from a height. [[#Lightly Obscured]] conditions reduce visibility: rain reduces maximum visibility to 1 mile, and fog reduces it to between 100 and 300 feet. Outdoor terrain determines the distance at which characters encounter other creatures. The **Travel Terrain** table gives suggested encounter distances for different types of terrain. **_Visibility at Sea._** From a ship's crow's nest, a lookout can see things up to 10 miles away, assuming clear skies and a relatively calm sea. Overcast skies reduce that distance by half. [[#Lightly Obscured]] conditions reduce visibility just as they do on land. **_Visibility Underwater._** Visibility underwater depends on water clarity and the available light. Use the **Underwater Encounter Distance** table to determine the encounter distances underwater. **Underwater Encounter Distance** | Visibility | Encounter Distance | | ------------------------- | ------------------ | | Clear water, Bright Light | 60 feet | | Clear water, Dim Light | 30 feet | | Murky water or Darkness | 10 feet |