Part 6: Adventuring ☰
In I&A, there are 3 levels of brightness: bright light, dim light, and darkness. Each affects how characters perceive the world around them, which is mechanically represented by how they affect Perception checks and combat. The effects of each level of brightness are detailed below.
Bright Light. In bright light, characters can see everything perfectly well, and have no penalties to Perception checks or attack rolls unless otherwise stated.
Dim Light. Dim light causes Perception checks to be made with disadvantage, however attacks are made as normal.
Darkness. In darkness, a character is considered blinded, and remains that way until they enter an area that is at least dimly lit.
If a character has infrared vision, they can use 4 actions at any time to change their vision from normal (light-based) sight to infrared (heat-based) sight. What this means is that that creature can see the amount of heat anything in their visual range gives off, such as a creature’s body heat or the heat of footprints left behind on a cold surface. It is important to note that certain surfaces and materials (such as fog and glass) are opaque in the infrared spectrum.
Usually, this will allow them to see with relative ease in dim light or darkness, but not always; if everything in their environment gives off the exact same amount of heat, then this will not help them very much. Additionally, they cannot perceive natural color while seeing in the infrared spectrum, which may work to their disadvantage depending on the situation.
In bright light, depending on the source of the light (such as the sun or an intense flame), the creature may be blinded while facing the source of the light, as the heat of the light overwhelms their infrared perceptions; if the source of the light gives off little or no heat, then this is not an issue.
A creature with darkvision perceives natural darkness as dim light, and natural dim light as bright light.
A creature with arcane darkvision perceives both natural and arcane darkness and dim light as bright light.