Battlemap
The Blasenhallen
The green mist carries the last breath of a people who fled from the deep.
The Blasenhallen are a ruined Sahuagin residential and breeding quarter arranged around a circular corridor. Their overturned nesting pools, abandoned food stores, and hurried warning marks suggest that the inhabitants fled from something rising beneath the ruins. Green poison vapor leaks from the cracked foundations and flows through channels toward deeper parts of the dungeon.
The Blasenhallen are cold, damp, and rank with old salt, rotting kelp, and the metallic odor of dried blood. Green vapor periodically seeps from floor cracks, hissing through shallow channels toward the deeper chambers. Faint clicking echoes around the ring corridor, sometimes joined by the distant scrape of something hunting in the dark.
â Threat
Monster 5, a reef-stalker known as the Greenjaw, now uses the Blasenhallen as a hunting ground. It has learned that the poison vapor drives prey from hiding and follows movement through the water channels. The creature is not the original terror that frightened the Sahuagin, but its presence makes every chamber dangerous. Deeper below, something older may still be listening through the flooded cracks.
History
The Blasenhallen were built by the Shell-Tide Sahuagin as a communal dwelling, hatchery, and food-processing quarter beneath the coastal ruins. Their priests blessed the breeding pools while warriors guarded the ring corridor and maintained channels that carried seawater through the complex. Years ago, the Sahuagin began carving warnings after a creature from the lower depths entered through the foundations. The evacuation was swift, leaving food, hatchlings' charms, and sealed reserves behind.
Encounter Table
CRA pair of Sahuagin deserters searches the halls for food and survivors. They know several warning signs but fear the shrine at the deepest point.
A pale, eyeless eel with a lamprey mouth swims through the vapor channels and emerges from any nearby puddle.
These carrion crabs are covered in mineral plates and drag scraps of armor through the corridor.
A wounded juvenile Greenjaw circles the ring corridor, testing the party before fleeing toward room 5.
Rumours & Whispers
Sahuagin still live beneath the coastal ruins, but they refuse to return because something hunts by smell instead of sight.
Green mist has begun leaking from village wells during the lowest tides.
A noble's signet ring was seen among the trophies of a beast that lives below the old ruins.
The Sahuagin left entire stores of food behind, which means they fled faster than any war party could have forced them.
An old tide-priest's mask can supposedly open a door that does not appear on any map.
Quest Hooks
Quest giver: Mara Venn, a desperate village net-mender
A fisherman's child vanished near the coastal ruins after following pale lights beneath the tide line. Tracks lead to the Blasenhallen, where the Greenjaw has dragged victims into its hunting grounds.
A coral-handled spear, 75 gp, and safe passage through the coastal marsh
Quest giver: Professor Ilyan Quill, an obsessive antiquarian
A scholar wants proof that the Sahuagin abandoned the ruins because of a deeper threat, not because of an ordinary war. The warning symbols and hidden escape route may confirm the theory.
A translated map of Dungeon 2 and access to the professor's library
Quest giver: Dessa Rook, a nervous relic dealer
A merchant's sealed cargo contains fragments of a Sahuagin relic stolen from the ruins. The relic reacts to the poison vapor and points toward the hidden supply vault.
150 gp, one rare pearl, and a favor from a coastal trade guild
Quest giver: Brother Caldus, keeper of the tide shrine
The green mist has begun appearing in village wells during low tide. Destroying the Greenjaw may stop the spread, but the true source lies beyond the concealed door to Dungeon 2.
A blessing that grants resistance to poison for one day and a consecrated silver charm
Corridor Notes
Dried tang mats cling to the walls like brittle skin, hiding faded Sahuagin tally marks and scratched warning symbols.
Shallow water channels cut through the floor, carrying intermittent streams of green, salty poison mist toward the lower chambers.
Bone hooks remain fixed in the walls, many still holding scraps of shell armor, fish leather, or desiccated bundles of herbs.
Broken ceramic jars and overturned storage baskets crunch underfoot, making stealth difficult unless travelers move slowly.
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