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
unknown
Death World
A death world, known only from a passing mention in Conquest of Armageddon (chapter 8, page 121, the chapter that brings the Rustung Armoured Fourth into the Plague Marshes of Armageddon's Equatorial Jungle). Canon records its class and nothing else.
Era Indomituspost-Rift
[RECORD LOST]
No record for this location in Era Indomitus.
Position
Map frame: 931, 471.3 in the archive's 0–1000 disk space (core at 500, 500).
Distance from the core: 432 units ≈ 46k light years, east of the galactic core.
Height above the disk plane: -5.0 units — invented thin-disk jitter, deterministic per record. No published source gives any location a z coordinate.
System: Derwynia System
Books set here
1 title in the reading tracker touches this record. 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/Derwynia (read directly in a browser on 2026-10-02): 'Derwynia is a Death World', infobox Class 'Death World', every other field blank, sole source Conquest of Armageddon (Novel), Chapter 8, pg. 121; Lexicanum Planets_(List) agrees (Death World, pg. 121). The same page range carries the Rustung Armoured Fourth (Lexicanum Rustung_Armoured_Fourth, ch. 8 pgs. 121-122), so the mention sits in the Plague Marshes chapter. NAME-COLLISION CHECK: no index record uses the name and the page carries no disambiguation note.
segmentumhigh
null: the infobox leaves segmentum, sector, subsector and system blank and the page files the world under Segmentum Unknown.
gposlow
inferred: NAMED but never located, so no segmentum is claimed and the record sits on the unsurveyed rim at the generator's rim_xy('derwynia') = [931,471.3] (build_locations.py's rim_xy evaluated on its own, reproducing heliogabalus [930.6, 442.4], chevreuse [931.5, 388.0], kallash [759.0, 848.6] and solemnus [482.4, 950.8]; the script itself was not run). The position carries no information and must not be read as one. Z -5 is the zPolicy value (compute-z.mjs derwynia 931 471.3).
classlow
'death', LOW, and said plainly: Step 5a2 forbids copying a Death World tag over a page's own terrain words (Nocturne, Medusa), but Derwynia's page publishes no terrain, climate or colour words at all, so there is no description to read instead. The dataset's death palette is a green jungle, the commonest kind of death world in the fiction and the one this book is itself set in. Reopen and repaint if any source describes the surface.
eraslow
m41 only, the era of the book that names it; the mention is undated. Allegiance 'unknown': no affiliation is published.
systemIdlow
editorial: 'derwynia', the world's own name; no system, star or other body is published. No survey authored (no-system-survey): the world is MENTIONED, not the book's setting.