Magic systems

Blood magic is the means, possession the result: blood magic tethers a demon to its user (Eamon). Crowbrook's arc: survival by blood magic -> tethering demons for strength -> contracted hosting -> witness courts to police it.

From the books

Wards, blood and luminarite in Luna

When Eamon's transformed father attacked in the Trade District, Seraphina Thorn spoke the Old Speak ward "Vox Veneni Obscuro", taken from pre-Luminarite crypt scripture. It raised a thin, sickly-green barrier that held under the creature's claws. Balorin Dawnbringer answered with a High Elvish battle blessing calling on luminarite to drive back the shadows.

In Luna, blood magic is a forbidden art, and King Aurelion dismisses it as Godless filth from Crowbrook. Eamon's father turned to it in desperation, and Eamon later used it to escape the cathedral. It left a trace in the streets that Ferrin could feel after the boy had passed. Usso calls luminarite a pretty poison that turned the King's eyes gold. At the Festival, Fae visitors wear dull anti-arcane cuffs.

Fae power

Fae power meets the body through the birth brand of one of four Houses: Phoenix (fire), Kraken (water, healing and current), Gorgon (stone and weight) and Sylph (air, storm and lightning). Feeling drives it, and strong feeling draws hollowborn. To stop dangerous emotion from spilling, the Fae take Hush, made from grey-white fungi that grow where old fear has soaked into the ground. Cross-House bonds are forbidden. A Phoenix and Sylph pairing is the worst, because air feeds fire. Kraken healers call on Mora only when ordinary current cannot keep a body alive, and the price lasts: after one such healing, Neris's gift would no longer turn inward to heal her and answered the patient instead.

Runeblades

Highlander runeblades are forged from red ore and are neither Fae glamour nor blood magic. Luminarite does not silence an oath. Waking a blade is a conversation with everything its bearer claims to be. As one old First Blade puts it, a runeblade does not punish losing but false carrying. Branok's burden-blades seal black corruption beneath red rune-lines. The first took. The second split on the binding stone when its bearer heard her dead son's name, and black smoke poured from the crack in a child's voice. Even so, Luna's priests mistake a runeblade's red light for blood magic.

Sable, a woman from Crowbrook, explains that demons are not one kind. Blood magic feeds certain kinds and oaths attract others, but shame attracts nearly all of them.

Possession under law

Crowbrook treats possession as a matter of law. Manus Farthing's studies identified three speakers in every opening, the host, the passenger and the witness, and a fourth role for whoever paid for the conditions and stayed away when the consequences came. Soldiers' bunks carry permission cards recording who may wake or restrain them. Father Cassian Veyr insists that grief is not permission and that a promise to do "anything" is no permission the Chain-Keeper recognises: the act must be named. Under the same reasoning, household charms such as ward teeth were reclassified as transfers once every protection had to name both who benefits and whose body pays.