The Phlegethon is a large, fluvial phenomenon located within the OTHERWHERE, notable for its highly unstable geography and unique biochemical composition.
Characteristics
The Phlegethon typically measures approximately 1.5 km in width and maintains an average depth of 15 m. It manifests as a fully formed river, complete with banks and flow direction, despite lacking any conventional hydrological source. The river exhibits no observable evaporation, and its volume remains stable throughout its temporary presence at a given location.
Composition
The Phlegethon is composed entirely of blood. Analytical sampling has confirmed the presence of haemoglobin and deoxyribonucleic acid (DNA) from a wide variety of iron-based lifeforms, including currently living species, extinct organisms and entities with no known biological counterparts. Human DNA is frequently detected among its components, and individual blood samples do not appear to cohere to any singular biological donor. The river maintains a constant temperature of 38°C. Notably, blood samples from the Phlegethon are immune to Haemolacerosis, and is universally compatible with all blood types in case of transfusion, regardless of species.
Behaviour
The Phlegethon is non-static. Approximately every 168 hours (7 days), the river undergoes complete spatial relocation, disappearing from its current site within seconds. A new spring subsequently forms elsewhere in the OTHERWHERE, at a location that appears to be entirely random. There is no known limitation regarding terrain, proximity to other landmarks, or frequency of reappearance in previous sites.
During each manifestation, the river flows continuously and without volume depletion, maintains a consistent elevation and pressure, and resists diversion, damming, or extraction attempts beyond superficial collection Even massive-scale harvesting operations do not appear to affect downstream flow or total volume.
Observational studies suggest a shared genesis mechanism between the Phlegethon and Haemocarbon. Haemocarbon shards often spontaneously grow along the riverbanks during the Phlegethon’s presence. The process of Haemocarbon crystallisation appears to be catalysed by proximity to the river.