Seba (an egyptian term for Star) are a kind of Vessel that was once utilized through the use of True Name magic by the Akhem-Urtu. In contrast to the other five types of relics used by the guilds, Seba are no physical objects. Instead, they are ideas, songs, masterpieces without form or substance, and frequently without location.
Without the influence of a mummy, most Seba remain unbound, patterns of Sekhem inscribed outside of space and substance similar to a Temakh. On occaison, these patterns become condensed and manifest themselves in an event known as a Convergence. A Manifest seba has the form of semi-liquid hieroglyphs revolving around and through one another like planets in an orrery. They still have no substance to speak of, but the Arisen are able to perceive them, as are some other supernaturals with the ability to perceive the hidden (although they rarely catch more than a glance if they have never been in contact with Seba before). Amkhata too can sense them, but are not able to interact with them.
Legends tell that the sky above the City of Pillars was illuminated by hundreds of manifested Seba that the Akhem-Urtu guild had brought forth. The followers of the Lost Guild are able to claim these seba as their own. Binding a manifest seba requires a knowledgeable occultist to speak the occult formulae and precise Iremite spells to claim the relic, adding it to her own True Name as a formal addendum. Afterwards, the Arisen suffers a curse and enjoys a benefit similar to other Vessels. When the mummy enters the death cycle, the Seba are cut loose from his soul, drifting again through the material world until they converge. Some Deceived, however, have found ways to utilize Seba in order to allow their cultists to revive them quickly. There are also ways to bind a seba to oneself beyond a single Descent, by making it into a Keshina.
A convergence can happen in two ways; through the cosmic interplay of Fate and Sekhem, or through artistic masterpieces made by mortal hands. Seba formed by artworks linger for a short period of time at the location were they were first formed before they are carried away by Sekhem. Since the Akhem-Urtu have lost the ability to produce creative art on their own, most work with their cults to inspire the formations of Seba in the population, scavenging them in the moment that they converge.
Cosmic Seba are something else entirely. Products formed by Fate, these Seba are among the rarest and most powerful objects to be found, reminding the Deceived that Sekhem is not confined to this world alone. Like comets, they travel across space, rarely converging on Earth, often in the time of a Sothic Turn.
- , p.102-109