Trace Portal

Portal tracing allows a caster to follow the path of a previous portal long after its closure. The ability is especially useful when tracking fleeing magic casters, although clever mages have developed counters to slow their pursuers or even prevent the trace.

Effect

Portal tracing allows a caster to ascertain whether or not a portal was cast in a nearby location within the last year, whether the current location was an entry or exit point for the last individual to use the portal, and eventually the location of the other side of the most recently cast portal in the area. Those skilled in Portal Travel can also cast a portal to parallel this path, although once completed this new portal will override any traces of the prior portal.

Side/Secondary Effects

The caster must remain uninterrupted while channeling the spell, as any distraction will at best break the trance and at worse leave their consciousness separate from their body, floating at the time and place of their location within the trace while they were interrupted. Many portal tracers rely upon allies to guard them during their channeled trance with the intent to prevent possible interruptions.
If the caster is merely pulled from the trance they can restart the trace from the beginning. If their consciousness was stranded their spirit and mind can still be reunited but the spellwork required will also overwrite the traces of the prior portal, rendering portal tracing inconclusive. This leaves any rescue attempt with a choice of which is more important, the trace or the tracer.

Manifestation

If portal travel was initiated within the last hour an individual capable of portal tracing will sense it subconsciously at the back of their mind, a faint feeling of a fresh flow of magic, similar to the sensation of a draft through a poorly insulated window. They can consciously activate this ability to extend the duration back up to a year, with the feeling growing weaker the further in the past the portal occurred. Talented users can even use this to estimate when the portal was used, although this will only provide an approximation.

Portal Tracing

Sitting, kneeling, or laying down is recommended for the caster's safety. When tracing the path of the portal the caster will feel their spirit leaving their body, similar to the feelings experienced during Astral Projection except with the added sense of insignificance and vulnerability, as if they are a small part of a large whole. They will catch various glimpses of the past and present throughout the multiverse of Fillimet, with no clues as to when or where these glimpses occur, before finally zeroing in on the opposite end of the portal. They will also feel a deep sense of welcome or farewell depending upon whether their current side of the portal was the entry or exit point.
Casting a portal to follow this path can be done if the magic user is also skilled in Portal Travel. Upon completion of the portal the caster is no longer required to maintain the trance, although they will need to continue to channel magic for the portal itself until its closure, unless they had already made other arrangements to maintain the portal independently.

Observing the Trace

To the casual observer it is impossible to discern whether the caster is portal tracing or astral projecting, as both spells result in a similar trancelike state. Those who are also naturally attuned to Metamagic may feel an increase in the flow of nearby magic but most observers, even magic users, will feel nothing themselves.
If the portal tracer also cast a portal to follow the trace there will be a sudden flash of light and sound as the space between the portal's entry and exit points are reconnected, resulting in a portal of the selected size. Otherwise observers will merely see the caster exit the trance.

Related School

Metamagic
Interdimensional Magic

Effect Casting Time

Experts can cast the spell in as little as fifteen minutes, while those simply learning the ability may take upwards of two hours to correctly complete the trace.

Applied Restriction

Portal tracing requires an expertise in detecting magic through Metamagic. Unlike most other magical schools the branches of Metamagic require an individual to already possess a natural attunement to the ability. Training can increase the strength and control an individual can exert when casting spells within their own innate metamagical abilities, but the spells cannot be learned by those without some level of attunement.
The spell will also only work on the most recently cast portal within the area. Any new portals cast within several meters will override all traces of the prior portal.

Further Reading