Exploration
Exploration involves delving into places that are dangerous and full of mystery.
Adventuring Equipment: As adventurers explore, their equipment can help them in many ways. For example, they can reach out of the way places with a Ladder, perceive things they wouldn’t otherwise notice with a Troch or another light source, bypass locked doors and containers with Thieves tools, and create obstacles for pursuers with Caltrops.
Vision and Light: Some adventuring tasks – such as noticing danger, hitting an enemy, and targeting certain spells – are affected by sight, so effects that obscure vision can hinder you.
Obscured Areas: An area might be Lightly or Heavily Obscured. In a Lightly Obscured area – such as an area with Dim Light, patchy fog, or moderate foliage – you have Disadvantage on Wisdom (Perception) checks that rely on sight.
A heavily obscured area – such as an area with Darkness, heavy fog, or dense foliage – is opaque. You have the blinded condition when trying to see something there.
Light: The presence or absence of light determines the category of illumination in an area.
Bright Light: lets most creatures see normally. Even in gloomy days provide Bright Light, as do torches, lanterns, fires, and other sources of illumination within a specific radius.
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: 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.
Special Senses: Some creatures have special senses that help them perceive things in certain situation.
Blindsight, Darkvision, Tremorsense, Truesight.
Hiding: Adventurers and monsters often hide, whether to spy on one another, sneak past a guardian, or set an ambush. The Dungeon Master decides when circumstances are appropriate for hiding. When you try to hid, you take the hide action.
Interacting with Objects: Interacting with objects is often simple to resolve. The player tells the DM that their character is doing something, such as moving a lever or opening a door, and the DM describes what happens. Sometimes, however, rules govern what you can do with an object.
What is an object: For the purpose of the rules, an object is a discrete, inanimate, item, like a window, door, sword, table, chair, or stone. it isn’t a building or a vehicle, which are composed of many objects.
Time Limited Object: When time is short, such as in combat, interactions with objects are limited: one free interaction per turn. That interaction must occur during a creature’s movement or action. Any additional interactions require the Utilize action.