This archive tracks four layers. A record present in 1 of them (M41) is silent in the rest, and says so.
The Horus HeresyM30–M31
[RECORD LOST]
No record for this location in The Horus Heresy.
Age of the ImperiumM32–M40
[RECORD LOST]
No record for this location in Age of the Imperium.
The 41st Millenniumpre-Rift
contested
Blood Angels memorial world, ruined; battleground of the Arkio Insurrection
A world of the Phaedra System, the centre of the Phaedra Campaign, the bloodiest war the Blood Angels had fought since the Horus Heresy; in honour of their losses the Ecclesiarchy granted it to the Chapter, and it was left mostly dead and ruined as a memorial to the battle. In late M41 Arkio, hailed as Sanguinius reborn, summons Dante to an audience here, and Chief Librarian Mephiston comes to judge him instead: Sabien becomes the battlefield of the Blood Angels' civil war, with the Word Bearers waiting in the system. Deus Sanguinius is set here.
Era Indomituspost-Rift
[RECORD LOST]
No record for this location in Era Indomitus.
Position
Map frame: 119.6, 734.3 in the archive's 0–1000 disk space (core at 500, 500).
Distance from the core: 447 units ≈ 47.5k light years, south-west of the galactic core.
Height above the disk plane: 1.9 units — invented thin-disk jitter, deterministic per record. No published source gives any location a z coordinate.
System: Phaedra System
Books set here
1 title in the reading tracker touches this record, 1 of them as a primary location. Titles link out to the tracker.
Every fact in this record, and where it came from. Editorial derivations say so.
identityhigh
wh40k.lexicanum.com/wiki/Sabien (read directly in a browser on 2026-10-02): 'a world of the Imperium administered by the Blood Angels'; System 'Phaedra System'; Class 'Memorial World'; Tithe Grade Aptus Non; 'the center of the bloody Phaedra Campaign, and was awarded to the Blood Angels in respect of their heavy losses in its defenses. Today, the world remains mostly dead and ruined'; 'later ... the center of the Arkio Insurrection' (Deus Sanguinius chs. 6-7). https://wh40k.lexicanum.com/wiki/Phaedra_Campaign: 'the largest loss of life for the Chapter since the Horus Heresy', after which 'the Ecclesiarchy granted ownership of Sabien to the Blood Angels' (Deus Sanguinius). NAME-COLLISION CHECK: Lexicanum full-text search for 'Sabien' returns only this world and pages about the Blood Angels novels; no index record uses the id or label.
book-joinhigh
PRIMARY for Deus Sanguinius (blood-angels::ba-rafen::2): the publisher's description names 'its final and bloody conclusion at the memorial world of Sabien' (Lexicanum Deus_Sanguinius_(Novel)), and Lexicanum Arkio, Arkio_Insurrection, Sachiel and Rafen place Mephiston's arrival, the duel, the ruined-cathedral fight and the battle with the Word Bearers there (chs. 9-14).
segmentumhigh
wh40k.lexicanum.com/wiki/Sabien infobox: Segmentum, Sector and Subsector all 'Unknown'; category 'Segmentum Unknown'. No segmentum is claimed.
classmedium
DEAD, medium. Painted from the page's own description, 'the world remains mostly dead and ruined, a reminder of the fierce battle waged there' (Lexicanum Sabien), and the 'ruined cathedral' of the climax (Arkio, ch. 12): a battle-blasted, lifeless grey world, which is what this dataset's dead palette draws. 'shrine' (Cybele's palette, pale bone plains with gilded peaks) was refused although Lexicanum Arkio and Red_Fury_(Novel) call it a 'Shrine World', because that and the infobox's 'Memorial World' are categories, and nothing describes tended shrines on its surface, only ruins.
gposlow
inferred: Lexicanum's Sabien infobox has Segmentum, Sector and Subsector ALL 'Unknown', and no page names a neighbour, bearing or theatre; its system is named (Phaedra) but that system has no page and is located nowhere. There is nothing to place this world against, so the record claims no segmentum and sits on the unsurveyed rim at the generator's rim_xy('sabien') = (119.6, 734.3), reproduced from build_locations.py's own fnv1a/CORE (checked against Nurth's stored point). The position carries no information and must not be read as one; nor does its distance from Shenlong or Cybele, which no source gives. Z 1.9 is the zPolicy value (compute-z.mjs sabien 119.6 734.3).
erashigh
m41 only: the Phaedra Campaign is 'sometime in M41' (Lexicanum Phaedra_Campaign) and the Arkio Insurrection '~900s.M41' (Arkio_Insurrection); Deus Sanguinius is filed M41 before the Great Rift. Allegiance 'contested' for the battle the book is set in. No source says anything of Sabien in hh, aoi or indomitus.
systemIdhigh
phaedra-system: Lexicanum Sabien's System field reads 'Phaedra System' (no page of its own). NOT the bare id 'phaedra', because Lexicanum's Phaedra is a different place, a Dark Coil planet (hatnote on Phaedra_Campaign), and a later record for it must not inherit this system.