Caves of Corrosion
LEVEL 1: ADMINISTRATION LEVEL
A-1) Entrance Tunnel: The entrance to Biggarswith Hollow stands half-sunken in a hillside of jagged rock, its weather-worn timbers stained a sickly green. The faint tang of metal hangs heavy in the air, and a metallic, acrid bite stings your nostrils with every breath. Rusted mining carts lie overturned like forgotten toys, their wheels coated in a thin, iridescent film. A low groaning creak echoes from deep within the mine, as if the earth itself were shifting beneath the weight of something unseen. Faintly, you hear the distant drip of water — steady, deliberate, and far too loud for mere condensation. A-2) Foremans Office: This cramped office is in disarray, with a split desk spilling papers soaked in greenish fluid. A torn mining map hangs on the wall, its features unreadable and claw-like gouges scar the doorframe leading out.- Feature: A scrawled entry in a ledger mentions "strange tremors, worse than before" just before the entries stop abruptly.
- Strongbox Loot: The strongbox is covered in corrosive acid. A player which attempts to unlock it takes 1d6 acid damage. DC 15 Thieves' Tools contains 25 gold pieces, 4 gemstones (worth 50g each), and 2 potions of healing.
- Note: The medical bay is not well stocked or complete. Mostly designed for isolation of sick miners, bandaging cuts and slinging broken limbs.
- Feature: A player with a passive perception of 14 or greater will notice a faint movement from one of the bodies — a subtle twitch of a hand or a weak groan. If the players approach, they will see that this dwarf is still alive, though barely. Otherwise a player who succeeds on a DC 14 Perception/Investigation check will notice the same thing.
- The players may make a DC 13 Medicine check to recognize that Thorin is severely injured, suffering from acid burns on his face, particularly around his eyes. They also realize that while his wounds are not immediately fatal, he will die without assistance. Stabilizing him requires magical healing or a successful Medicine check (DC 15) using a healer’s kit or improvised materials.
- Personality: Thorin is hardy and stubborn but also deeply shaken by the events. His voice trembles as he speaks, not out of fear but from the sheer pain of his injuries. He’s slow to trust the party initially, but if the players show kindness or patience, he will open up.
- Motivation: Thorin wants to know if the other miners are alive. He is desperate to hear good news but will react with sorrow if the party tells him otherwise. His ultimate goal is survival — he just wants to get out alive.
- Thorin does not recall many specific details of the incident, only that he heard an ear piercing screech followed by a loud crash. As he turned to look in the direction of the noise, he felt a searing pain in his face and the world went black as he fell unconcious.
- The foreman of the mine had been growing concerned about something, though he did not know what. He ventured into the mines on his own the day before the attack.
- Later that day, these large, chittering bug-like creatures began coming from some lower parts of the mine. They collapsed several side tunnels on the minin level to cut off their movements and blocked off the tunnel leading below the mining level.
- It wasnt his call, but the foreman was in the lower levels when they collapsed the tunnels.
- Feature: The crank on the winch is damaged and will need to be replaced before the lift can be operated. Players may salvage the wreckage to repair the winch with a successful DC 13 Investigation check.
- Failing to to salvage an appropriate crank will require the players to climb down the supply lift. They may make a DC 14 Athletics check to climb down the cable, on a fail the player falls 30ft and takes 3d6 bludgenoning damage.
- The crank at the bottom is still intact and can be cranked to activate the mineshaft.
Mining Level
M-1) Supply Station: Broken crates and rusted tools lie scattered across the floor, and the faint smell of rot mingles with the sharp tang of acid. A warped shelf tilts dangerously, its contents spilled onto the ground below.- Loot: 2 intact Pitons and 50ft of usable rope - DC 14 Investigation reveals a hidden compartment beneath a barrel which contains 1x potion of acid resistance and 1x potion of fire resistance as well as 1x scroll of Tidal Wave
- Feature: If the players search the desk they will find the foremans notes scattered about. Give them the handouts from the "Scattered Notes" section.
- 3x - Tithonoloth Tunneller Drone
- 2x - Tithonoloth Soldier Drone
- 3x - Ankheg
- 1x - Umber Hulk
- DC 15 Athletics or Acrobatics check to attempt to cross the rails. Failing a check will result in the player falling 30ft to the pit below and taking 2d6 bludgeoning damage.
- Roughly halfway across, the rail will give way slightly. The player nearest to the center must succeed on a DC 14 Athletics saving throw, or fall 30ft to the pit below and take 2d6 bludgeoning damage.
- If any player falls into the pit below, the creatures will attack.
- Loot: an intricate looking beard bead that has a strange mental weight to it(see Bead of Enduring) can be found beside an Artisans Kit.
Trap! - While moving through the corridor between M-5 and M-6
- As the players walk through the narrow corridor, when one of the players reaches the Y junction of the mine cart track, green acid erupts from the ground. Any creature within 20ft must make a DC 15 dexterity saving throw, taking 3d6 acid damage of a fail or half as much on a success.
- DC 13 investigation - Preliminary checks will determin that a tunnel created by one of the bug creatures had a pool of acid inside that was then covered by the nearby tunnel collopse. The players movement disturbed the earth surrounding it which caused the pressure from the gasses to erupt outward.
M-6) Miner's Bunkroom: Ragged bedrolls and dented footlockers are scattered across the floor. The air smells of damp cloth and acid, and faint scratches mark the floor near the back wall. Hidden Loot: DC 13 Investigation - A pair of silver rings in a hidden compartment beneath the lid of one foot locker.
- One mundaine worth 25gp
- One Ring of Spell Storing - 1x Cure Wounds, 1x Bless, 1x Guiding Bolt
- Loot: A healing salve (acts as a Potion of Healing) can be found in a storage cupboard (Investigation DC 13).
- Utilizing any physical or magical resources at their disposal.
- A player with darkvision would be able to faintly make out a large pool of water, directly below the opening.
- A creature who enters the pool will recieve 1d6 acid damage upon entering it, as well as for every 10ft they swim in it.
- If a player succeeds on a DC 17 Perception check, they will notice
Character Creation
The copper mines of Biggarswith Hollow, hidden within the sprawling Planes of Alduun, have fallen into an unusual quiet. Once filled with the clatter of pickaxes and the hum of miner's songs, the tunnels now echo with nothing but still air. Shipments have ceased, and no word has come from the foreman or his crew. Tasked with uncovering the cause of this silence, you and your party are called to venture into the depths. But as the shadows deepen and the weight of the earth presses in, it becomes clear that something more than broken tools or fallen stone has halted the work below. Edition: 5eLevel: 7
Stats: Point Buy
Gear: Starting gear plus your choice of 1x set of mundane armour
Magic Items: 5 Points + 1x +1 Weapon, Shield OR Armour
- 1 Point - Potion of Healing
- 2 Points - Uncommon Magic item
- 3 Points - Rare Magic item
Resources
Maps Admin Level Mining Level Final Chamber Items Stat Blocks- Tithonoloth Tunneler
- Tithonoloth Soldier Drone
DM Notes
Background & Context- An Adult Black Dragon has moved into the mines and taken it over as its new layer
- The black dragons activity in the region has caused a stir in a local colony of Tithonoloth, resulting in the colony dispersing and interupting minin operations of several of the regions mines
- The foreman of Biggarswith hallow has been receiving correspondance from another nearby mines foreman, detailing strange occurances happening within their mine
- As some of these occurences begin presenting in Biggarswith Hallow as well, the foreman investigates one of them deeper in the mines. During his investigation, the Tithonoloth arrive at Biggarswith Hallow as well, prompting the other miners to collapse several tunnels, including the one leading to the lower levels where the foreman went, in order to limit the space in the mines
- Soon after, the dragon moved in, killed the miners and claimed the lower levels of the mine for his layer.
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