This archive tracks four layers. A record present in 1 of them (HH) is silent in the rest, and says so.
The Horus HeresyM30–M31
imperium
Battleship, Guilliman's flagship on the road to Terra
A battleship of the Ultramarines Legion and Roboute Guilliman's flagship as the Ultramarines try to reach Terra before the Warmaster's forces invade it, with the Navigator Maesa Pytheas of House Pytheas aboard (Spear of Ultramar, Chapter 1).
Position: Charchera System (Charchera System) Roboute Guilliman's flagship on the Ultramarines' race to Terra through the Ruinstorm, which runs through the Charchera system Cited in Spear of Ultramar
Age of the ImperiumM32–M40
[RECORD LOST]
No record for this location in Age of the Imperium.
Position in this era: [RECORD LOST].
The 41st Millenniumpre-Rift
[RECORD LOST]
No record for this location in The 41st Millennium.
Position in this era: [RECORD LOST].
Era Indomituspost-Rift
[RECORD LOST]
No record for this location in Era Indomitus.
Position in this era: [RECORD LOST].
Position
A mobile record: it carries a position timeline rather than a fixed point. The archive places it in 1 of the four eras (HH); each era section above carries that era's entry.
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/Ultimus_Mundi (read directly in a browser on 2026-10-02): 'a Battleship in the Ultramarines Legion during the Horus Heresy. It served as the Primarch Guilliman's flagship as the Ultramarines attempted to reach Terra before it was invaded by the forces of Horus', citing Spear of Ultramar, Chapter 1; https://wh40k.lexicanum.com/wiki/Known_Vessels_of_the_Ultramarines (the same, ref 10); https://wh40k.lexicanum.com/wiki/Maesa_Pytheas (its Navigator, Chapter 1). NAME-COLLISION CHECK: no index record uses the name. Distinct from macragges-honour, Guilliman's flagship at Calth and in the Indomitus Crusade.
archetypehigh
'battleship': Lexicanum calls it a Battleship and names no class.
positionsmedium
hh, the Charchera system: Guilliman's flagship for the crossing, and the Ultramarines 'had to pass through the Carchera System' and fight there (Lexicanum Battle_of_the_Carchera_System, Chapter 2). That the flagship itself is in the system for the battle is inferred from its being the primarch's flagship for the voyage; no permitted source places a scene aboard it there.
erashigh
hh only: the one book that names it is set as the Heresy nears its end. Nothing is on file for any other era.