Detect Lifesig

Life Signatures (shortened to lifesig) can be detected in a radius around the caster by using Magic to cast a "Detect Lifesig" spell. This is an Art of Perception. This will allow for increased perception of any living beings nearby. This can also be used to tell how healthy someone is, since someone who is severely wounded or sick will have a slightly faded life signature than normal, healthy living beings.

There are different aspects to this, and a magical spell can be manually crafted to work in many unique ways. As with most magical spells, the more complicated the spell is, the more an in-depth understanding of the physics behind it will need to be - or enough resonance with a relevant Universal Concept needs to be felt.

Signal Cognition Interface (SCI)
There are a few modes of how the detection can work. A spell can be crafted to use multiple of these SCIs at the same time, but it gets exponentially harder to focus on balancing all these at the same time.
 * Vision - if Detect Life is cast using the eyes as the SCI, then the magic user can highlight life forms using an aura of their choosing by making their eyes more sensitive to a specific wavelength of life upon detecting the life form. This will restrict the detection to vision. Using an advanced form of super infrared imaging, it is possible to detect lifesig through walls, albeit at a reduced distance. This is Dianna's form of SCI for processing lifesig.
 * Hearing - If Detect Life is cast using the ears as the SCI, then the magic user can immediately tell any life forms depending on sounds that their lifesig emits. This allows for automated wall permeation and is easier to cast thus costing less mental energy, although it causes the spell to only register the life form when they are making any kind of sound audible to the user. Ear SCI works because sounds are tagged with a lifesig, and can be traced back to their original location depending on how the difference in audible volume from one ear to the other. This is Katie's main form of signal cognition for lifesig.
 * Touch - If Detect Life is cast using touching sensation, then the magic user can tell whether something is alive or not by touching it. This is the easiest method for SCI.
 * Vibration - If Detect Life is cast using vibrations, then the magic user can tell whether something is alive or not by feeling vibrations of lifeforms. This allows detection of lifeforms who are even sneaking absolutely silently from behind, because their footsteps will cause enough vibration to be picked up. An example of a character who has this is Binary.
 * Direct "Sixth Sense" Cognition - This allows the energy to be infused directly as knowledge, giving the effect as if they "just know" whether anyone is within a radius. This is the most mentally taxing mode of SCI for Detect Lifesig.

Base detection distance
The distance of the detection spell boils down to raw mental power - if processing of the life signature is slow, the radius will be lower. If someone is having trouble doing this spell or is a first time caster, they may only see it up close at first.

The caster can use some mental tricks to prioritize differently. For example, the caster can reduce the SCI speed to be able to process more radius. With the Vision mode of SCI, this would appear as if the flashes of coloured auras would only appear every 5 seconds while the caster works on deciphering the next batch of signals. However, for close quarters, the caster might decide to focus on a closer distance (intentionally reducing the detection distance) in order to have a clear, continuous aura that they can follow.

Levels of Lifesig Differentiation
There are different levels of finesse when detecting life, each of which are exponentially difficult, especially combined with more complicated forms of SCI.


 * Tier 1: Lifesig can be detected: Very small life forms are impossible to see, although this can be used to detect whether cells are alive or dead under a microscope, as well as to see whether someone in sight is alive or dead.
 * Tier 2: Lifesig can be detected + Their sentience can be determined
 * Tier 3: Lifesig can be detected + Their exact appearance and who they are is known
 * Tier 4: Lifesig can be detected + Can tell who they are + Can figure out what are the Universal Concepts they resonate with the most

Automaticity
Although it costs far less mental energy overall to put Spell Focus on just detecting life, Detect Lifesig is one of many spells that can be automated. This is much like turning the spell into a "passive" spell, which allows the caster to focus on casting a different spell while still being able to detect life forms.