The Dark Sea Region is an expansive, ice-cold ocean located on the Dark Side of VOI 700 D. Covering an estimated 700,000 square kilometers — an area roughly the size of Mongolia on Earth — it is the largest known body of water on the Dark Side and remains one of the most mysterious and least explored regions of the planet.

Unlike the Regions of the Habitual Belt, where perpetual twilight allows for some warmth and vegetation, the Dark Sea is locked in eternal night, with its waters hovering just above freezing due to the planet’s lack of a natural heat source. Large portions of the ocean are covered in thick ice, while others remain liquid due to deep geothermal activity. The absence of sunlight has led to the evolution of unique bioluminescent marine ecosystems, making the Dark Sea one of the strangest and most hostile environments on VOI 700 D.

The western shores of the Dark Sea are bordered by the Ralar Region, where the active volcano Ralar releases geothermal heat into the ocean, creating a rare microclimate along the coastline. Here, pockets of warmth support life, forming thermal vents and tidepools where flora and fauna thrive in defiance of the harsh environment. This coastal area, referred to as the “Ralar Bay and Shore,” is the only officially explored section of the Dark Sea. Exohuman expeditions during the Beta Age mapped a sea corridor up to 10 miles from the shore, with depths ranging from 15 to 95 meters. Beyond this, the sea remains an enigma.

To the north and east, the Dark Sea extends into absolute darkness, with unknown depths, ice formations the size of mountains, and unfathomable trenches that plunge into the abyss. There are no confirmed Exohuman expeditions that have successfully mapped these waters, and the Native Tribes do not claim this region, believing it to be the realm of unseen spirits.

The Dark Sea Region is defined by its icy waters, frozen archipelagos, geothermal coastlines, and abyssal trenches. Its unrelenting cold and lack of light have shaped its unique geography and climate.

The Ralar Bay is a narrow band of coastline. It is geothermally active due to proximity to the Ralar Volcano.

• Temperatures here range from 0°C to -10°C, making it one of the warmest areas on the Dark Side.
• Volcanic activity creates tidepools, hot springs, sulfur vents, and sections of open water.
• Supports limited but rich ecosystems, including bioluminescent algae and thermophilic organisms.

Most of the sea is covered in thick ice sheets ranging from several meters to hundreds of meters thick.

• Temperatures drop to between -40°C and -70°C depending on altitude and exposure.
• Ice formations drift slowly across the ocean surface, hiding abyssal trenches and hydrothermal anomalies beneath.
• Depth of the sea outside the explored corridor remains unknown; theories range from shallow subglacial plains to oceanic chasms.

• Coastal Shoreline (Ralar Region Border): A rare geothermal coastline where volcanic activity from Ralar Volcano warms the waters. Weak ice formations often break apart due to geothermal shifts.
• Frozen Ocean Expanses: It is assumed that the majority of the Dark Sea is locked beneath thick ice. Cracks and crevasses occasionally offer glimpses into the dark waters below.
• Subsurface Trenches and Geothermal Anomalies: Hypothesized trenches and vent systems may house extremophile life deep below the ice, but remain unconfirmed.

Life in the Dark Sea Region is extremely rare, limited to a few specialized organisms that thrive in the warmer coastal pockets and subglacial zones.

• Thermophilic Algae – Found in warm melt pools near the volcanic coastline, forming thin, bioluminescent layers beneath the ice.
• Geothermal Fungi – Similar to those in the Ralar Region's Geothermal Caves, these fungi feed off volcanic minerals and cling to thermal vents.
• Deep-Sea Chemosynthetic Bacteria – Hypothetical extremophiles that might exist in hydrothermal vent systems deep below the ice.

The Dark Sea's frozen and sunless expanse limits animal life to a few highly adapted species that thrive in thermal refuges or beneath the ice.

• Abyssal Predators – Potential deep-sea creatures lurking in unexplored trenches.
• Ice-Dwelling Scavengers – Small, crustacean-like creatures feeding on organic material trapped in glacial layers.
• Glacial Stalkers – Hypothetical apex predators that roam the coastal ice, adapted for hunting in complete darkness.
• Dark Sea Flyers – Mysterious winged creatures rumored to nest in geothermal caves along the shoreline.
• For a detailed list of creatures, see Known Wildlife of the Dark Sea.

The Dark Sea Region is completely uninhabited, apart from temporary Exohuman expeditions in the Beta Age and occasional Outlaw activity in the Gamma Age.

• Scientific Outposts (Beta Age only) – Small research teams occasionally visit the volcanic shoreline to study subglacial conditions and extremophile life.
• Illegal Activity (Gamma Age only) – Some outlaw groups are rumored to use ice caves along the shore as temporary hideouts, though permanent survival is unlikely.

The Dark Sea Region is a mysterious and largely unexplored frontier, making it a blank canvas for Dungeon Masters. Apart from the narrow stretch of shoreline near the Ralar Volcano — explored up to ten nautical miles into the sea during the Beta Age — the vast majority of this icy ocean remains unmapped and unknown. Depth measurements exist only for Ralar Bay, ranging from 15 to 95 meters, while the deeper ocean beyond is subject to speculation, myths, and fear.

Worldbuilders should distinguish between the Ralar Bay Microclimate, shaped by geothermal activity, and the Frozen Expanse, which lies beyond and remains in absolute darkness. While the bay offers tidepools, hot springs, and ice caverns suitable for survival encounters, the deeper sea beneath the ice presents an entirely different world — one filled with bioluminescent organisms, pressure-resistant sea creatures, and ancient abyssal predators.

Adventures in this region can explore themes of isolation, survival, cosmic horror, and first contact with the truly alien. Under the ice, where no light ever penetrates, players may discover forgotten wrecks, ancient relics, or massive sea beasts adapted to the crushing darkness. The deeper you go, the less the rules of the surface world seem to apply.

• Complete Darkness – The Dark Sea is perpetually pitch-black, requiring specialized vision equipment or bioluminescent guides.
• Unstable Ice Sheets – The frozen ocean is riddled with hidden crevasses, making traversal extremely dangerous.
• Subglacial Terrors – If anything lives in the deep, it remains undiscovered and highly dangerous.

• The Lost Vessel – Rumors persist of a vanished Exohuman research ship, its wreckage still drifting beneath the ice.
• Deep-Sea Behemoth – What if something enormous lurks in the depths?
• Ancient Relics – Could the Dark Sea hide ruins or artifacts of an unknown civilization?

• VOI 700 D
• Dark Side
• Known Wildlife of the Dark Sea Region

Known Neighboring Regions:

• Ralar Region (Northern and Western / Dark Side)
• Vazhak (Eastern / Dark Side)