Senses define how you can perceive the world around you. Many skills and abilities are defined by senses, Awareness and Investigation being the two most prominent.
The Senses category includes those senses you can use to Observe a target. You may have other senses, but they're not precise enough to allow you to pinpoint a target or their movements.
Unless noted, all characters have the Vision sense.
Senses include:
Darkvision: You can see in complete darkness, though only in black and white. Darkvision can be natural, or the result of technology or magic (see: night vision goggles). You lose this sense in areas of normal light, as your vision is overwhelmed, as well as if you are blinded or dazzled. Darkvision does not have a range.
Hearing: You can hear the environment around you through echolocation. You lose this sense if you are deafened or silenced.
Scent: You can identify the environment around you through olfactory clues. You lose this sense if you are exposed to powerful scents. Scent usually only extends to a certain Range, and only reveals creatures with an aroma.
Tremorsense: You can identify the environment around you through feeling the vibrations of a solid surface. Tremorsense only works if you are on the same surface as the target. Tremorsense is negated by flight or levetation.
Vision: You can see the environment around you. Vision comes in two forms: standard vision and low-light vision. You lose this sense if you are blinded or dazzled.
Low-Light Vision can see in Dim Light as well as if it were Normal Light
Standard Vision cannot see in Dim Light, and treats all creatures and objects in Dim Light as if they have Concealment.
Senses come in 3 qualities: Precise, Imprecise, and Vague
A precise sense can detect the world in nuanced detail. If you can detect a creature with a precise sense, you have no penalties in targetting them. You can detect a creature automatically with a precise sense, unless that creature is hiding or obscured by the environment, in which case you can use the Seek action to detect the creature.
Imprecise senses cannot detect the full range of detail a precise sense can. You can usually sense a creature automatically with an imprecise sense, but it gains the Hidden condition against you unless you can locate it with your Precise Senses. It might be undetected by you if it’s using Stealth or is in an environment that distorts the sense, such as a noisy room in the case of hearing. In those cases, you have to use the Seek basic action to detect the creature. At best, an imprecise sense can be used to make an undetected creature (or one you didn’t even know was there) merely hidden—it can’t make the creature observed.
A character also has many vague senses—ones that can alert you that something is there but aren’t useful for zeroing in on it to determine exactly what it is. At best, a vague sense can be used to detect the presence of an unnoticed creature, making it undetected. Even then, the vague sense isn’t sufficient to make the creature hidden or observed.
Vision is the most important sense for most humans and other supernatural creatures. The amount of light in an area can affect how well you see things. There are four levels of light: bright light, normal light, dim light and darkness.
A source of light emits normal light out to its listed range, and sheds dim light to double that radius. Unless otherwise noted, illumination doesn't emit bright light.
Bright light is light strong enough to cause people to squint in pain, put on sunglasses, or sheek shelter. This includes a bright, snowy day, or an area illuminated by floodlights or powerful industrial lights, or the Moon's surface in direct sunlight. Most creatures gain the dazzled condition in Bright Light. A creature can’t use Stealth in an area of bright light unless it is invisible or has cover.
Normal light is a normal, partially cloudy day, or a well-lit building. In normal light, creatures and objects can be observed clearly by anyone with imprecise vision or better.
Areas in shadow or lit by weak light sources are in dim light, including outdoors on a clear night, or inside a building lit only through windows. Creatures and objects in dim light have the concealed condition, unless the seeker has darkvision or low-light vision, or a precise sense other than vision.
A creature or object within darkness is hidden or undetected unless the seeker has darkvision or a precise sense other than vision. A creature without darkvision or another means of perceiving in darkness has the blinded condition while in darkness, though it might be able to see illuminated areas beyond the darkness. If a creature can see into an illuminated area, it can observe creatures within that illuminated area normally. After being in darkness, sudden exposure to bright light might make you dazzled for a short time, as determined by the GM.
Terror Sense: A horror can detect the terror wafting off sapient creatures. A horror can detect all creatures within 1 range suffering from the Frightened condition. This is a metaphysical sense, and manifests to the horror as the sound of a thudding heart, ragging breath, or frightened whimpers.
In gameplay, there are four different states of awareness that you can have with regard to another creature, which determine, for example, whether you surprise it when you engage it in combat or whether you can target a creature with an attack. These states of awareness are described below.
When you are unaware of another creature, you don’t even know it is present. Generally, this occurs because the creature is hidden, you failed your Awareness check to notice it, and the creature hasn’t yet performed any actions that would alert you to its presence. You cannot directly attack a creature you are unaware of, but it is subject to area effects.
When you are aware of another creature’s presence, you don’t necessarily know exactly where it is. Typically this occurs when the hidden creature has taken some action that revealed its general presence in the area but has successfully used Stealth since then to hide its exact location. If you have succeeded at an Awareness check to notice a creature with an imprecise sense, you are aware of the creature’s presence. You cannot directly attack a creature if you are only aware of its presence, but it is subject to area effects affecting its location.
In order to directly attack such a creature, you must pinpoint its exact location with an additional Awareness check to Seek. If this check is successful and you are using an imprecise sense to pinpoint a creature, you become aware of the creature’s location (see Aware of Location below). If this check is successful and you are using a precise sense to pinpoint a creature, you are observing the creature (see Observing below).
When you are aware of a creature’s location, you know exactly where the creature is located, but you still can’t observe the creature with a precise sense such as vision. Generally, this occurs because the creature is hidden but you have succeeded at an Awareness check to Seek for the creature with an imprecise sense, or because the creature has dove behind Cover that obscures your line of sight. You must at least be aware of a creature’s location in order to attack it directly, though it is considered to be Concealed from you. It is, however, subject to area effects affecting that location.
When you are observing a creature, you can directly perceive the creature with a precise sense. Generally, this occurs when a creature is visible, when the situation makes it impossible for the creature use Stealth to hide, or when you have succeeded at a Awareness check to search for the creature using a precise sense. You must be observing a creature to use a ranged effect that targets a specific creature without requiring an attack roll to hit. You can also make normal attacks, including ones using ranged abilities, against creatures that you are observing. Again, it is subject to area effects that affect its location.
A creature currently being observed can’t attempt a Stealth check without first breaking that observation. To break observation, the creature must either mask itself from your precise senses (with darkness, fog, invisibility, or the like, but not with effects such as displacement that still leave a clear visual indicator of its location), move somewhere it can’t be observed (a place with cover, for example), or use Deception to create a distraction to momentarily break your observation of it.