Over a century has passed since reality ripped apart. Over a century since Guilliman was saved from the precipice of death millennia in the making. Over a century since the Indomitus Crusade – the Imperium’s first death spasm – began.
The Realm of Ultramar, home of the last Primarch, has fought off countless invasions during this time by myriad forces of the heretic and xenos. Each conflict has seen the warriors of the Imperium victorious, but every battle saps their strength bit by bit. The Black Crusade, the Plague War, the Vengeance Campaign. In spite of all, the core of Ultramar remains secure but even this mighty Realm-within-the-Realm crumbles at the edges.
One such afflicted region is known as the Geminids, a binary star system in the east of the Ultramar sector. These twin stars orbit each other, close enough for sub-light travel in reasonable time but far enough for each to harbour their own system of planets. Two of these planets are actively inhabited: Acragas orbits Gemina-A, and Himera orbits Gemina-B.
Both worlds were once paragons of the Ultramar realm, housing a mixture of cultural sites, production facilities and military installations. They nominally remain in Imperial control, though in reality several strategic sites across the twin system have been seized by hostile forces looking to turn the system into a base of operations in the Ultramar sector.
At the start of the campaign, players will be split into two teams: the forces of Order and Disorder. The forces of Order are working for the broad goal of bringing the binary system back under full Imperial control, while the forces of Disorder are working to sever it entirely. They are not necessarily “allies”, but at least share similar broad goals. Each player should use the same Army Faction for the duration of the campaign.
Control of the Geminid binary system is represented by Strategic Assets. Each Asset has a value associated with it, ranging from 1-3, representing its importance to the ongoing war effort. Control of these Assets will determine the eventual victor of the campaign and will be gained or lost in battle. Some will be designated as Home Assets – these are Assets that cannot be lost.
You can see the related Reddit post here.