Underdark is a designer drug developed by alchemists in the employ of Inibis Valmeia (but whose identities are unknown). It is a viscous and opaquely black liquid that might be mistaken for crude oil if not for the streaks of dark purple that can usually be seen coursing softly through it.
The primary intention of the drug is to deliver a scripted, pre-defined, extremely vivid and lucid dream to the user.
Details & Effects
As The Party (less Grihymm Phrahdrandon) can attest, Undardark is completely tasteless when imbibed. According to Inibis, it originally tasted "absolutely foul" and required additional engineering to perfect its currently tasteless form.
The main effect of consuming the substance is twofold. It first puts the user into a deep sleep (which can take as few as thirty seconds to onset) and then subsequently delivers a highly specific, pre-defined dream that appears to allow for a total lucidity on the part of the user. This allows them to interact with it however they conciously choose.
Each individual batch is engineered to induce a specific dream. Users partaking simultaneously of the same batch are able to share the same dream, interacting directly with one another therein. Although logic and reason can be totally circumvented within these dreams, and although the effect is staggeringly vivid, the user does not awaken prior to the conclusion of the scripted dream or their death within it.
The waking memory of these dreams has been described as "so realistic as to be disorienting," and the sleep induced by the drug does not appear to be at all restful.
The substance can be purchased for a premium in the Cauldron district of Necine (and it is exported elsewhere by certain airship-owning entrepreneurs) or it can be otherwise commissioned to induce a specific dream of the buyer's choosing (though this does not come cheap).
The substance itself is not physically addictive but its existence effectively allows a person to escape (however falsely or temporarily) to another reality of their choosing. This makes it an extremely attractive hobby for those who can afford it, and people have often been seen sleeping in the streets of Necine after having administered the drug.
The drug has been linked to a growing number of suicides that have followed the drain of monetary savings or the life-ruining effects of sleeping through every day (or simply sacrificing normal sleep to the dream-addled one induced by the drug). Others still simply find that they lose their taste for their own reality, preferring the dreams instead.
The Party's First Experience
Although Grihymm Phrahdrandon elected not to partake, choosing instead to watch over his friends in unfamilar environs in the company of Inibis herself), all other members of The Party accepted the volta's invitation to experience Underdark for themselves.
In their shared dream, the party was placed into the shoes of Acaelican heroes of legend as they attempted to release The Void Song from its prison during The Demon War.
Castian-- who was responsible for displaying the events of this dream to Inibis and other partygoers--titled this dream "A Verse to the Void Song," and it apparently served to enterain Inibis and to "kill time" while the Perish Day prisoners were hunted down in the night.