NOTE : This is an unfinished, and living document. It is subject to change based on community feedback as well as official histories released in future sets. I'd love to see others contribute to the secret histories as well. I will do my best to remove discrepancy and redundancy that may exist, but the intertwinings of the houses is complicated. This is a work of speculative fan-fiction, all of the houses, cards, and official lore are copyright FFG. Thanks go mostly to those who've created the world and illustrated it.
Herein lies the secret histories of the known Houses of the Crucible.
House Logos
Logos adopt the knowledge of other factions through learning and exchange. The division within House is far greater than appears. Though there are those who seek unity and mutal understanding within the faction, the divide between theoretical knowledge and applicable science has caused contempt in the great schism of the House. Logos is at war with itself, though any overt attack from outside forces is likely to bring them together once again.
The Mechanists have obtained alliances with the mighty houses of Brobnar and Sanctum through exchange of technology, primarily the technology found among Brobnar, and the cybernetic armor utilized by Sanctum. Brobnar views Mechanists as the stronger force within the house with physically manifested power. While the continuance of armor is of utmost importance to Sanctums religious conversion among humans from various factions.
Logos Theorists have had little choice but to ally themselves with Dis and Mars as the only two factions who might work against the might of the enemies arrayed before them. Dis and the Theorists share common enemies in Sanctum. Much of the art for Logos seem to display major thematic elements of Dis, Mars, and Sanctum.
House Sanctum
Sanctum's abhorrence of threats to the theocracy are likely the root cause for the hatred of that faction. Sanctum is the light while Dis is the Darkness. Sanctum is good where Dis is evil. It is possible that this hatred, along with potential Shadows agents among the human element, and the fall of angels past have lead to corrupt elements within the faction.
The House's wars with Brobnar are likely due to the ineffectiveness and lack of potential for proselytization in the faction. But some shared enemy within the faction of House's of Logos and Dis may unite them, if only for a short time. Sanctum see Theorists as counter to their own cause, as there view of pure logic counter to their dynamic of good vs. evil is a threat to their religion. The Mechanists, however, are a potential source of the cybernetic armor which they possess, and unlikely to meddle in such affairs as religion.
Sanctum has the card Sigil of Brotherhood, which seems to indicate it has some influence or mutual admiration within elements of all current houses. If this is true, than Sanctum's light may be more far reaching than we know. This unity is likely heavily political, and something like the UN in our world. Politics and the need to communicate in an open forum are likely to be found in any House, even among those seen as counter to this idea. Their political sway may be seen as an alternate weapon in religious conquest.
House Mars
As the most recent House, it's unlikely that House Mars has forgotten the decline of their empire due to their war with Humans of Earth. Humans of any faction, especially the Humans of Untamed which seem to possess the most dreaded of Human weapons, The Common Cold, are well known. Brobnar is seen as a threat to their subjugation of the Crucible, but Houses Sanctum, Untamed, and Shadows, along with humans among the Mechanists of Logos, are seen as a threat to their very existence.
The most bitter enemy of Mars, and only match in secrets, is House Shadows. House Shadows has no in roads into Mars, and vice versa. Their overwhelmingly humanoid appearance makes them the most dangerous among their competition for conquest in the Crucible. Dis is likely to use their influence in this rivalry to lead these two factions into pain and anguish in their shared future.
Since their entry into the Crucible, Logos has seen them with suspicion and potential. Ozmo's abilities recognize the threat and possibility on Mars has lead to his understanding them more than any other being in the Crucible. He knows much of the history of Mars and is the only Diplomat to have been known as welcome among them. EMP Blast is an experiment to subjugate the robot forces when it comes to that. Mars knows open warfare against House Logos will unify the divided forces, and they must ensure conquest in this new realm.
Their rapid technological advancement are due to concepts shared in an alliance with the Theorists of House Logos. They most likely view Theorists as merely a means to advance their cause. They have a vested interest in keeping them alive and divided from other elements within the Logos faction. Since Theorists seem to be ruled almost exclusively by Machines with little desire for conquest in the physical realm, Mars has little to fear from them, but are in need of more powerful and disruptive forces.
Mars have their own resources and technology and aren't in need of the Mechanists "inferior hardware." However, there is synergy between the Theorists ability to advance the sciences. The Crazy Killing Machine, especially, seems more likely to be a Martian technology adopted by Theorists than a Logos technology. The shared use of vats often found in card art for the two houses indicate shared or parallel technological advancement.
The Martians don't understand the motivation of Dis, and view their realm as unconquerable and inconsequential. A secret triple entente with House Dis and the Theorists exists, but is unlikely to be view among any side as permanent or unbreakable at any given time.
Mars one desire is to physically subjugate the planets of other races, perhaps bending them to their will or mutating them for utilization, due to their physically hindered bodies. Brobnar is the first priority in their conquest, and there is a big reason for that. They want to use the subjugation of the hordes of Brobnar to protect them from human elements within other factions.
House Brobnar
Based on art and history, Brobnar will destroy anything they view as less than them, which is pretty much anything that can't display raw power. They see this as mere sport and have no great master plan. The tribal nature of the house leads to direct conflict among the tribes, and unification is only for the purpose of even greater wars. They fight Sanctum because of the challenge and view those among them who've taken to physical manifestations with some amount of respect. They harbor some loathing of the of incorporeal elements of Dis, Sanctum, and Untamed.
Both Sanctum and Brobnar have flavor text referring to contempt for those not wearing pants, and a shared contempt for Logos, though Brobnar doesn't seem to mind the technological advantages that might be afforded them by the Mechanists.
They view House Shadows as frail, but know the threat of their ability to steal Amber as a threat. Similarly, they look at the new Martian House as puny and fearful. They neither understand, nor seek to understand any threat in House Mars. They would be glad to destroy the house, if only for the joy of watching them squirm.
Brobnar are direct and not particularly complex. They know their strength is strength, and they view weakness as a plague that must be eradicated.
House Shadows
House Shadows doesn't seek overt war, but take more indirect means to harvest amber from their opponents. They are in direct opposition to Sanctum's pious overtones within their house of "sin." Based on art and theme, they utilize an association with Dis to further their political and cabalistic control. The Key of Darkness leads directly to Dis.
Their use of assassins and cut throat thieves is well known by all Houses, but much less is known about their motivations. Their will to power is through seemingly indirect means that allow them to steal from the other houses, often without retribution. Their love of amber is based mostly on their utilization of it as capital to their shrouded intent for the future of the Crucible.
House Dis
Their means and ends are fear and pain. They dominate through corruptive forces and the ability to undermine the other houses. Dis seek influence among the humans. Perhaps they will be great stealers of souls and chaos magicians Dis in the future, though their frail souls are easily susceptible to being overwhelmed. They find in the proving grounds of Logos, Sanctum, Shadows, and Untamed the potential for powerful harbingers and Chaos Magicians.
Fallen Brobnar are to be found among their ranks, because Brobnar care little for what cannot be demonstrated. The lack of exchange with the Brobnar leads to resentment, which is the corruptive force among them.
The soulless Theorists of Logos provide robotic Imps and have diminished the appearance of major threat with farcical descriptions of them as less Demon and more a naturally occurring form of parasite. Dis will utilize their alliance with the Theorists to seep into that house's humans.
Though they have thus far been able to manifest in humans their ultimate potential as harbingers of the soul, they utilize the other houses as experiments and proving grounds. Humans in Shadows and Untamed, have proven to be the most susceptible to Dis' overtures. Mars' suspicion of all things foreign has kept the wolves at bay, though they will find in roads in that house as well as House Shadows through diplomacy.
Though it seems Dis' avowed enemy is Sanctum, there is likely some infiltration and pleasing fractioning of that house, with corrupted forces that grow weary of the piousness of Sanctum and would rather descend into darkness. The harbingers of souls known as the Four Horsemen are secretly in league with the forces of Dis. Furthernore, the knights of Sanctum's realm have often enough found their path to **** in the ranks of Dis. If you find heretics, you will find lost souls. Among the more human elements of politics, bureacracy, and diplomacy corruption of souls is found most readily, but Sanctum's indoctrination leaves humans within far more susceptible to reaping than desire for greater power.
House Untamed
<to be written>
Edited by debiant