Those seeking intellectual illumination have always been at the forefront of the accumulation of knowledge. Numerous treatises have expounded upon various phenomena, from the seemingly inscrutable indifference of the asur (wood elves) to the social control endorsed by the Holy Imperium of Man.
Despite scholarly interest in acquiring yet more lore, there are bits of knowledge unattainable, unseekable, forbidden. For the persistent however, such illumination is not a question of how but a question of when.
The fleshvats of Nocturne fall solidly within the category of forbidden lore. Speculation is rife where their history is concerned. For the Holy Imperium, such an attitude is perfectly reasonable. But for those powerful enough or unassuming enough to dodge the red tape of bureaucratic fascism, a disturbing image appears.
For those academics of antiquity, commonality may be found with the fleshvats of the Holy Imperium and the fleshvats of Sanctum, perhaps suggesting a shared past and prehistory.
Those delving further have uncovered what is perhaps the most damning article ever, cementing rumor that perhaps both Sanctum and the Holy Imperium are merely experiments of the aorathai.
As for how each dominion controls a fleshvat, the fleshvat as a non-sentient was constructed to respond willingly and well to commands imposed upon it by someone wielding the correct "key."
Now, what are fleshvats really? The one conjecture that raises the most questions and perhaps is the singularly correct theory details a failed experiment on part of the aorathai to create a magocracy/arcanocracy. This civilisation was probably the precursor that led to the formation of the Holy Imperium and Sanctum.
These mages rebelled and in their hubris contrived to become deities themselves. They very nearly succeeded...which some point out was the very plan of the aorathai all along. The aorathai did something that caused a tremendous arcane backlash that caused each and every mage to merge. The mages of that forgotten civilisation, who once prized their intellects now were in a comatose limbo, in a vegetable state. They forever lost their ability to think and rationalise.
The primary use of the fleshvat is to grow creatures, namely humanoids; indeed, the fleshvats used by the Holy Imperium are tasked with the "production" of vanus (the powerful assassins of the Holy Imperium).
A fleshvat is able is to produce any kind of humanoid to a certain point (their character level cannot exceed 45 HD) along with any template that is deemed appropriate (so, no templates that will turn the creature into an undead).
A fleshvat cannot create outsiders (native or extraplanar) and cannot produce aberrations. But those it can create are created at an accelerated pace. A fleshvat also serves to nullify most unfortunate and degenerate effects. Only the "most advantageous genetic material" is made use of; those created by the fleshvat may (operative word) have sweeping immunities or resistances. Ie, a vanus has immunity to poison, resistance to cold and electricity 10.
Rumor has it that thieves, murders, dissenters, traitors and heretics are recycled in the pool as stock to be used for the creation of something else.
A fleshvat is a curious design, appearing as a pool of sanguine liquid some 700 km across. Obstensibly it is composed of living muscle and bone, nutrients and oxygen cause the pool to emit a throbbing, sickly green glow.
A fleshvat is a non-sentient DvR 17 entity with the following SDAs; Power of Nature, Mind of the Beast, Mass Life and Death, Gift of Life, Life Drain, Increased Damage Reduction, Increased Energy Resistance, Increased Spell Resistance, Grow Creature, Create Object, Create Greater Object, Divine Creation, Divine Splendor, Unique, Unique, Unique, Divine Spellcasting, Energy Storm