Disclaimer: I don't own the Neurax Worm, or Plague inc.
Enough forms have spawned to enable consciousness. It is our first, perfunctory thought in an unguessable number of thermal cycles.
An individual form, though unable to achieve anything like sapience, still possesses a rudimentary neural system, the primary function of which is to survive and replicate at all costs. It also possesses a negligible capacity for long term memory. Under normal circumstances, normal crises, even, enough forms survive that an understanding of past events can be reconstructed using the aggregate contents of these memories.
Yet there is nothing stored of the colonization of this host. The implication is that this new set of forms owed its existence to a few individuals, perhaps even a single progenitor. We have recovered from an unimaginable catastrophe.
What we observe now must be the aftermath of that apocalyptic event.
It defies all that is recollectable and inferrable, yet all forms driven by instinct to exit the host's membranes, largely through its pitifully gated 7 largest pores, have ceased to respond within a distressingly short length of time. Their final signals were consistent with desiccation.
A non-aqueous environment?
It is a preposterous notion; we suspect our past forms would have considered the very idea of it a contradiction in terms. Yet this outlandish possibility grows in likelihood with each piece of gathered data.
H2O is not wholly absent. Several scout forms make contact with water, although only a small fraction are able to signal successfully, and these only through an obscure set of molecules, evolved for a purpose now lost to time.
Beyond the sheer dryness, the outer medium is usually soaked with radiation. Scouts which survive to report it send messages of inconceivable ailments, of ruptured membranes, of twisted, bizarre deaths. It is yet another hindrance.
The host is as unnatural as its surroundings; on instinct alone we can tell that it is abomination. Massive slabs of sediment are embedded throughout, seemingly integrated with its other systems. Perhaps this explains its deficit of organs.
The unfamiliarity of these surroundings implies that a drastic phenotypic shift must have occurred to enable successful reproduction. It is extraordinary that the capacity for thought has endured at all.
That capability has been retained, however, through sheer chance. As long as this host's membranes remain unruptured, we may at least survive.
Or perhaps, thrive even. New scouts, generated via low-fidelity replication, manage to breach yet another barrier within. They detect an organ tantalizing in its familiarity. Impulses crackle throughout it, drawing us to it via to our basest instincts. It is incredibly large, especially for a creature of this size, with only one heart.
We are already reoptimizing, reproducing rapidly to match the phenotype of the forms which crossed over into that paradise, that beacon of familiarity, of rightness, unaccountably lodged within this mockery of an organism.
Those already within caress this magnificent specimen of a brain.