@Durin, this is a nitpick, but why was "First War of Expansion" chosen instead of something with the word "Crusade" in it? It seems a bit odd since
Lexicanum's description of a Crusade seems to match exactly to what the First War of Expansion was.
Differentiation
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... but seriously that's the main reason I can think off. Crusade also has quite a few religious overtones which might be another, but who knows.
Deadman's* Rock: The Governor's Bane
Taken with heavy casualties during the war of expansion, Dead Man's rock is a crucial world as it sits as a nexus of vital warp lanes which connects five of the other worlds in Subsector Gehenna together including the Magma world of Char. The only world that Deadman's rock is not connected to directly is in fact Mar Sara.**
With such a vital artery, so far out in the Trust space, the Trust Engineers payed special attention to the world that would most likely be selected as subsector capital in the future, heavily fortifying it even compared to the normal high standards of the Trust.
The system has seemingly never known the touch of human civilisation***, and was a true challenge to take as the number of orks concentrated here was astounding with incredibly well made defences by their standards fitting with its status as an orkish factory world. Eventually an Avernite strike team eventually acting on information given by Head Master Ridcully eventually breaking the orbital defences and allowing the Trust to leverage its might better on the world's surface.
The Rock itself is rich in metals, with the orks having made a good effort at extracting as much as possible to fuel their crazed schemes, the litter and debris of 13,000 years of orkish industrialisation and conflict scattered around as the colonists made their attempts to colonise the world. Ironically the mass pollution of the planet by the orks has resulted in a positive side effect, as the thin atmosphere the planet would have had has thickened to the point that an environmental restoration project**** similar to Midgard's would be possible in the future.
Not a planet in the strictest sense, the Rock is in fact the largest moon of an incredibly large gas giant, with several other large sibling satellites and a massive asteroid belt thick and ready for exploitation and trapping.
As with all Trust colonies the population is dominant Midgardian, however it has a wider range of immigrants from other worlds of the Trust due to its location as a cross road and resupply point for the rest of subsector Gehenna. Already disgraced Vanir noblemen, Avernite burnouts, Jotun explorers have decided to settle down there*****.
Defensively, the main hive city is the Deadman's Port. Built into the largest mountain on the moon, this strong hold is intended to both support ships in orbit and to defend against the large hordes of orks on the planet below. The orbit has been turned into a maze of death, with the planet taking advantage of the thick asteroid field to mine it extensively, with the combination of mines and asteroids estimated to be able to damage battleships, maybe even take them down if lucky.
Economically the world is doing incredibly well for itself, trade from all the nearby colony worlds has been flowing in as well as several productive mines having been established both in orbit and on the ground. The Adeptus Mechanicus presence has also been growing fairly quickly, led by Magos Daltius X2 a senior member of the Collegia Reconstructus, who is supervising the salvage operations on the world.
The most interesting industry of the Rock is salvage. The world was first controlled by orks during the Dark Age of Technology and constant rule by them since M32 has led to the planet being covered in scrap metal, with it being so thick in some places it forms miniature mountains. Most of this is only good as a cheap and quick source of metal to fuel the colonies growth, but buried deep it is hoped the remains of the Dark Age cities are still there. Certainly, scraps of technology have appeared, with a long broken impaler being recovered.
Then comes the real reason the planet is known as Deadman's rock. The Orks on the planet are both some of the stronger orks in the Subsector and the best equipped due to the bounty of scrap metal they have available to make their weapons of destruction. Though not as numerous as those on Korhal, they have managed to kill two previous governors, resulting in the Trust sending in their emergency governor.
Mira Han is of Muspelhiem by descent, possessing a shock of dark purple hair******, a large and intimidating bionic eye and a mind as devious and strange as a metal trap. Born slightly after the Death of the Emperor, she was noted as being brilliant, if eccentric. A military genius, with an intuitive grasp of combat Han was able to set records at the Trust officer academy as one of its first students, but her attitudes and strategies, which were incredibly unorthodox at the time, grated upon many of her teachers. Due to her skill, she was given command of a multi-unit task force, named the Marauders, later renamed Mira's Marauders, whose job was to act as harassment and support for other units during combat, being slightly outside of the normal command structure.
While an odd role, Han managed to thrive in her posting securing victories against many foes, most notably a Dark Eldar Arcon, who she is reported to have bitten the throat out off after it took her eye.
The main blemishes on her record are her lack of decorum at public events where she is frequently distracted or uneasy******* and one instance where she was court marshalled for drawing her weapon and placing the colonel of a regiment under arrest after the battle for Jotunhiem. While she was later acquitted, as later investigation by Saint Lin proved that at least a division of the colonel's men were corrupted thus making her decision more of an impromptu quarantine rather than malicious.
Her skills meant that she was put on a short list of "emergency" candidates that the Low Council created, in case of the death of a governor. While at the bottom of the list the rapid loss of two governors meant Han was sent to bring the Deadman's world to heel which she was able to do through judicious application of explosives and preemptive strikes. Skilled, devious and possessive, Mira Han considers Deadman's rock as hers and intends to keep it that way even if an entire Waargh should fall on the world.
*The original name of the world was considered, but the nickname had already stuck.
**A situation Governor Horner is reportedly most pleased with.
***According to the Muspel Archives the planet was colonised during the Dark Age of technology, but was taken over by orks several times during it and has not been held by humans since M32.
****Several Millenia of industrial pollutants have thickened the atmosphere to the point that it is much more suited for holding life…if that life can breathe carbon dioxide, which the Orks apparently can.
*****A rumour is that an incredibly rare Nilfar oddball, a Nilfar that displays enough interest in the rest of the Trust to go out and travel it of their own free will in short almost unheard off, has decided to settle on the world. Most dismiss this rumour as completely fanciful.
******A constant wonder for many that know her is whether or not her hair is dyed, or modified to look the colour it is. The only one who might know is Governor Horner and he is not saying a word on the matter.
*******On particularly impressive dinner thrown after the battle of Fyjol was interrupted by Han leaving halfway through to go visit Governor Horner who had been badly injured during the battle. Rumours (long denied as always) persist that this was the moment when their impromptu engagement became something more substantial.
And done.
@Durin probably not canon, but I had to do it.