This route is the reward for solving the Assembly Yard puzzle. It should feel like a clever, stealthy infiltration, emphasizing skills over brute force. The challenge here is navigation and avoiding detection.
The Descent (The “Keyhole”)
- Description:
“The seven-sided hatch opens with a low groan, revealing a cramped, dark shaft descending vertically. The air that rises smells of stale, filtered air, ozone, and dust that has been undisturbed for a century. A series of rusted rungs lines one side of the shaft, which is just wide enough for one person to climb down at a time.”
- Challenge: It’s a long way down (e.g., 100-150 feet). It’s not just a simple climb.
- A section of the ladder is broken, requiring a DC 13 Strength (Athletics) check to navigate the gap.
- A damaged power conduit arcs with electricity every few seconds, requiring a DC 14 Dexterity saving throw for anyone moving past it to avoid taking 1d10 lightning damage. This makes the descent a tense, timed challenge.
The Labyrinthine Conduits (The “Lock”)
This is where their schematic becomes invaluable. Instead of just one junction, we can make it a sequence of 2-3 choices to make them feel like they are truly navigating a maze.
- Description:
“The vertical shaft opens into a network of cylindrical maintenance tunnels, just tall enough to crouch in. Pipes and colour-coded conduits line the walls, and the low hum of dormant machinery is ever-present. The schematics show this is Junction Point Alpha.”
- Challenge 1 - The Coolant Line:
- “The path splits. According to the schematics, the left fork is marked ‘Diagnostic Access C-3’, while the right is a much larger conduit labeled ‘LV-07 Coolant Return.’ The schematic has a note next to the coolant line: ‘WARNING: Unstable temperature fluctuations.‘”
- Solution: The correct path is the cramped Diagnostic Access tunnel. Choosing the Coolant Return forces a DC 14 Constitution saving throw as a wave of intense cold or scalding heat washes through it, dealing 2d6 cold/fire damage on a failure (half on success) and leading to a dead end.
- Challenge 2 - The Sonic Cleanser:
“Further in, you reach a sealed pressure door. A panel next to it reads ‘Activate Sonic Cleansing Protocol Before Entry.’ The schematics show this leads to the correct path.”
- Solution: They can either endure the cleansing or bypass it.
- Endure: Activating it fills the next chamber with a deafening, high-frequency sound for one round. Anyone inside must make a DC 13 Constitution saving throw or be Deafened for 1 hour.
- Bypass: A successful DC 15 Intelligence check with Tinker’s Tools or Thieves’ Tools can override the lock and open the door silently.
- Solution: They can either endure the cleansing or bypass it.
Minor Security Measures (The “Tumblers”)
- Description:
“As you crawl through one section, you hear a faint whirring and clicking sound ahead. Peeking around a corner, you see a fist-sized, spider-like construct, a Cannith Repair Mite, methodically polishing the inside of the conduit with tiny mechanical arms, its single blue photoreceptor scanning back and forth.”
- Challenge: The party must sneak past one or two of these mites. This requires a group Dexterity (Stealth) check with a DC of 14.
- Failure: On a failure, the mite closest to the character with the lowest roll swivels its head, its blue light turning a piercing red. It emits a loud, screeching alarm tone for one round before scuttling away into a smaller pipe.
- Consequence of Alarm: “The alarm echoes down the tunnels ahead. You hear the distant, heavy ‘thunk’ of magnetic locks engaging in the room you were heading towards. Your stealthy approach has been compromised.” (This will make their final exit harder).
The Exit (The “Click”)
- Description:
“The conduit terminates in a heavy ventilation grate set high on the wall of a pristine, white, and silent laboratory. Through the slats, you can see workstations, strange arcane devices in glass cases, and containment units. You have a perfect, hidden vantage point to observe the lab before making your entrance.”
- Final Challenge: The grate is locked from the inside. It requires a successful DC 15 Dexterity (Thieves’ Tools) check to unlock its bolts silently.
- Failure: A bolt snaps or a tool slips, making a loud CLANG that echoes in the silent lab below, alerting anyone or anything that might be there.
- If the Alarm was Triggered Earlier: When they look through the grate, they see that two suits of Animated Armor, previously dormant in wall alcoves, are now active and patrolling the lab below, making a stealthy entry significantly more complicated.