GW releases Secret Level Lore tidbits - Spoilers for Space Marine 2
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Did you clock the colour of young Demetrian Titus’s eyes? Ultramarine blue – it was always meant to be.
The room where Sergeant Metaurus accepts the mission is an armouring chamber similar to the one you can see in the Armouring of a Space Marine video. You’ll note that his higher rank affords him access to one with a statue of Guilliman in it.
The planet the episode takes place on is called Zsah’Uj (no, we don’t know how to pronounce it either. It's probably easier to say with a beak). This world sits in the far west of the galaxy, not far from the worlds that feature in Warhammer 40,000: Space Marine 2, and the Deathwatch Watch Fortress where Titus served his penance.
After the drop pod lands, we see broken eggshells and a bit of parchment appear out of sparks; this area of the planet is a place where the veil between the Warp and reality is very thin, and some Tzeentchian Warp-i-ness has leaked in, including fragments from the Library of Lies – where all lies are recorded. That’s what the paper is, a fresh lie being told somewhere in the galaxy and catalogued in the Lord of Fate’s library. This closeness to the Warp also contributes to why their targeters and comms are not working properly.
Did you notice when Metaurus picks up a chunk of metal to shield himself against the punishing salvo of the traitor Leman Russ tank? That hunk of metal is actually a tilting shield from one of the destroyed war machines in the rubble nearby.
The High Priestess of the Tzeentchian cult is a mutated and highly gifted sorcerer who twists her foes’ minds against them. She had been resting within the orb of the statue’s staff before the Space Marines arrived, and you can see hints of her heretical carvings around its edges.
Once the idol and sorceress are destroyed, the disruptive power of the Warp is weakened, allowing the vox and other systems to reconnect to the Space Marine warship in orbit and target the shrine’s location with an orbital strike.
The knife Titus kills the sorceress with is the same one he was found with on the battlefield when discovered by Metaurus as a boy.
In Sergeant Metaurus’ HUD after the battle, you can see that he has a series of serious internal injuries: critical failure of his Larraman's Organ, Belisarian Furnace unresponsive, Oolitic systems inactive, and Sus-an membrane: primed. Similarly, his armour would no longer be fully sealed or void-capable as soon as he was stabbed. You can see the words "Atmospheric seal integrity compromised" in his HUD, so if that Sus-an membrane kicks in, Metaurus and his armour will both be in for repairs for a while.