Believed to be some of the largest living organisms on the planet, mushrooms and fungi occupy a strange and liminal space in how our two species can interact and coexist.
Given that they are - without exception - a carnivorous species, it is probably unsurprising that descriptions of Echocap Mushrooms do not lead with the distinctive milky-blue marbling of their gently rounded caps or the bleached-bone white of their squat and rigid stems. Instead, and unfailingly (present presentation precluded), people are told to first observe them as a haphazard bloom of growths protruding from the head of whatever unfortunate beast has consumed their spores. Producing and secreting a powerful topical analgesic as they form within neurological tissue and push out through the skull and skin, their prey feels nothing - and may not even be aware that there is something wrong - until the underlying web of fungus chokes their brain beyond functioning.
Maybe mistaking their planting for something more whimsical (mushrooms entangled in fur or pelt, perhaps?), or being believed to be a more benign, carrion-grown fungus, at some point someone deigned - or was desperate enough - to consume an Echocap, thereby discovering their more impressive properties. In addition to bridging the gap between the animal and plant kingdoms, mushrooms have sometimes been seen as having morbid associations with the rot and ruin in which many varieties thrive. These dual identities reach something of a shared apotheosis in Echocap Mushrooms; through some transient property or through the nature of their entanglement with the brain they become a repository for the memories of their host, making something essential into something physical and giving experiences a form that can be passed-on.
Echocaps copy the electrical and chemical patterns from the fibrous bundles of neurological tissues into their own and, in the process, become a psychophagic medium. An intermediary between what they have consumed and what consumes them, they must, at first, have seemed like particularly potent entheogens - ones that leaned heavily on associative expectations; pick a mushroom from the head of a wolf and live the experience of a hunt, of howling at the moon or prowling with a pack. Pick one from a sheep and ruminate on rumination and bitter, rechewed grasses. The chance to expand upon these discoveries would have been curtailed though, those early psychedelic pioneers would soon begin to realise that they were playing host to the next batch of mushrooms.
Where the numbing properties of the Echocaps might have kept other animals from noticing their changed appearance (and their limited intelligence would have spared them the dread of anticipating their imminent deaths), the same could not be said for the afflicted humans. The lack of sensation did not offset the ability to recognise and comprehend the ongoing mutilation and corruption of their flesh, nor lessen the innate and intellectual understanding that something deeply and dangerously wrong was happening, but the spread of the fungus was already inevitable and irreversible. Some slight reprieve was possible - cutting back the eruptions seemed to split the Echocap’s efforts between regrowth and further internal spread - but everyone infected knew that they had been given a death sentence.
It is unclear how someone came to discover that something so potentially dangerous could be made safe, its active spores denatured by charring or boiling whilst leaving its psychoactive effects only somewhat blunted, but it seems likely that they persisted because of the Echocaps’ potential ritualistic value. Properly prepared, they allowed practitioners of various naturalistic and zoolatrous religions to inhabit the experience of being an animal and, more importantly, to survive repeated visions. Primarily employed as such a tool by those seeking to mitigate the unnatural impurity of the socialised human soul by reconnecting it to a raw animalism that was considered essential to our forebears, an enterprising - albeit somewhat sadistically pragmatic - person eventually realised that the same mushrooms could be used as an interrogative.
Echocap Mushrooms were, essentially, weaponised; used as a potent and persuasive part of torturers’ arsenals in conflicts the world over. If someone refused to talk, they could be forced - or tricked - into consuming the mushrooms, at which point everything they knew would be made available in an innocuous-looking serving of fresh Echocaps. Torture, already the preserve of the cruel and the callous, took on an element of cannibalism (albeit via fungal proxy) that disquieted even many of those who had had the stomach for its already bloody rigors. Ironically, the practice developed a quasi-religious aspect - torturer as confessor - through the use of a resource previously reserved for rite and ritual; an absolute communion that gave the interrogator otherwise impossible insights into someone they had already damned.
This method for the extraction of information was - even disregarding the indefensible horror of it - far from perfect. The impressions that were received through the consumption of the neutralised mushrooms could be fogged or blurry, sometimes fragmentary, but were always less precise than the cleaner read of the raw and unfiltered alternative. That alternative - a perfect synthesis between the victim and the torturer - came at cost of mutual annihilation; a pair of sympathetically and symmetrically horrendous deaths that would perhaps engender a too-apt empathy. Most settled for the lesser of the two results, though there have been examples - fortunately sparingly few - of those willing to destroy themselves in the pursuit of information; suicide or martyrdom as, largely, a difference in perspective.
Over time the ritualistic consumption of Echocap Mushrooms has all but ceased; partially because of the decline of the faiths to whom they were of value and partially in favour of less volatile and potentially fatal alternatives, though they remain a part of a few, ever-dwindling religious practices. Their use in gathering information from enemy combatants and prisoners - or the threat of their use as a form of psychological torture - was formally banned in 1863 (per the shadow appendices to the First Geneva Conventions and their subsequent updates and amendments), leading to an even steeper drop in their deliberate cultivation. Absent such a deliberate hand in their proliferation, Echocaps have become increasingly uncommon; relegated to a grotesque footnote as they (hopefully) edge closer and closer to extinction.