Necromancer—an adept of the Nine Houses, born with the ability to control thanergy (the energy of death) and thalergy (the energy of life), as well as the ability to convert the latter to the former. There is no isolated genetic code associated with necromantic potential, nor the presence of any extra biological feature apart from heightened activity from organs we would otherwise mark as vestigial. Necromantic aptitude must be exercised in order to be used efficiently, and is strongest on a thanergenic planet (such as those typical to the Nine Houses). A very common side effect is physical weakness and an inability to keep and form muscle mass, though this has its genetic exceptions. Necromancy does not work in space or on board spaceships due to the way space disperses thanergy without a thalergy anchor such as a planet: necromancers are almost entirely personally powerless when travelling from planet to planet, though theorems (spells) they have created will last in some cases in deep space.
Cavalier—a swordsman of the Nine Houses who has sworn themselves to a specific necromancer. The lead cavalier in any House is known as the cavalier primary, and second to them the cavalier secondary; they are not ranked otherwise. Cavalier status must be awarded by the House, and a cavalier may keep their title in the Cohort. Who becomes a cavalier and under what rubric differs from House to House, but a cavalier cannot be fully considered to be so without a necromancer who has sworn the oath with them.
Thanergy—death energy. Planets and gaseous bodies in space usually produce thalergenic radiation. The sun and planets of the Nine Houses are thanergenic in character after the Resurrection. Thalergenic planets may be converted to be thanergy planets, i.e. dying planets, but almost never thanergenic (producing death energy but on a stable basis). Thanergy is produced by cellular death.
Thalergy—life energy. Most objects in the universe are thalergenic in character. Thalergy is produced by cellular growth and reproduction. Most planets, even ones without a biological mass of life, are thalergenic. Thalergy is produced by all living creatures.
Nine Houses—the name of both the empire and the system that comprise the Necrolord Prime’s home system. The Nine Houses came into being ten thousand years ago with the “Resurrection,” a response to the mass dying-off of the system’s planets and sun that destroyed all life. When the first necromancer—the Emperor—ascended, he resurrected the planets and the people to become the Nine Houses. Nine Houses territory only comprises the system; planets and systems that the Empire “shepherds” are not regarded as being extensions of home, especially because necromancers do not reproduce successfully outside the system.
Dominicus—the central thanergenic star of the Nine Houses system.
Bone magic—the school of magic chiefly to do with manipulating the extant thanergy of bones, or impregnating them with additional thanergy. Bones being the only known source of long-term storable thanergy, bone magic is to do with animating and “programming” bones (raised skeletons), manipulating inert or living bone, or forming bone into patterns it wants to fill (topological resonance). Bone creation—reproducing skeletal matter from a sample—is the ultimate end state of bone magic.
Flesh magic—the school of magic chiefly to do with manipulating the extant thanergy of flesh, or impregnating it with additional thanergy. Flesh is a conduit for short-term storable thanergy, and in the right circumstances provides immense thalergy and thanergy boosts to the magician. Flesh magic is wide-ranging, covering preservation, imbuing, manipulation, creation, and processing. Blood magic is a subschool of flesh magic, as the remnant thalergy and thanergy in blood makes it perfect for use in warding. Lymph magic is widely disregarded as a poor substitute. Flesh magic is also used for self-manipulation of the human body, either to make it perform better or to make it perform worse, often quite suddenly.
Spirit magic—the school of magic chiefly concerned with the River, ghosts, and revenants, as well as with liminal magic spaces and nexuses. Spirit magic is diverse, and can range widely from creation of anti-thalergy and anti-thanergy spaces (impregnation of spirit energy into non-River spaces) to manipulation of people’s souls, forming conduits to the River, to the conversion of another person’s spirit and thalergy to thanergy. It is also the school of magic that lets the living access the River, the afterlife space to which the dead are drawn. The subschool of River magic is practised only by the Emperor and his Lyctors.
The Locked Tomb—another name for the Ninth House, but also an area within the Ninth House. The Locked Tomb is the resting place of an unfathomable enemy of the Emperor, killed after the Resurrection and placed in the Ninth House in order to show it respect. There is a school of thought in the outer Houses that the Ninth House was never meant to exist in the long term, and that the Ninth House priests, nuns, and faithful worship the Tomb alongside the Emperor, rather than as being a sign of the Emperor’s might. What it contains has never been made explicit.
Lyctor—a personal servant, guard, and disciple to the Emperor. The Lyctors are undying, all-powerful necromantic saints whose aptitude endures even in space. In the early days of the Empire, they made it possible for the Nine Houses to act within the fullness of their power on thalergy planets; they also set steles throughout the galaxy, the necromantic means through which the Nine House fleet travels quickly through space without needing to use faster-than-light speed. Though there were originally seven full Lyctors, they have died over the years, none being as powerful or eternal as their Necrolord Prime.