RUST LOGIC
RED TIER

Verified for the August 2026 patch · updated Aug 20, 2026

Underwater Labs Guide — Card Modules & Loot Route

Underwater Labs' card rooms are modular: green rooms need a card + fuse, blue modules typically green + blue + 1 fuse, red modules a red card + 1–2 fuses for elite crates. Bring 2–3 fuses per dive.

Difficulty: hard · time on-site: 20–40 min · by RustLogic Staff

Bring exactly this

  • Green card ×1
  • Blue card ×1
  • Red card ×1
  • Electric fuse ×2
  • None — bring diving/sub logistics instead
Underwater Labs — puzzle circuit
Sub / moonpool Green module F Fuse the circuit Blue module F Fuse #2 Red module Up to 3 elites

No two Underwater Labs are identical — they’re bolted together from modules per map seed. So this guide teaches the pattern, not one floor plan: find the card rooms, read their tier, fuse their circuits, and work up the chain.

Before you go

All three cards if you have them, 2–3 electric fuses, a submarine (fishing village vendors), tight-quarters weapons, and meds. There’s no radiation — the sea and the scientists are the hazards.

The route pattern

  1. Dock at the moonpool. Surface inside the lab’s wet bay and clear the immediate room before leaving the water — scientists patrol right up to the pool edge.
  2. Scout before swiping. Walk the station and find its card doors first. Every lab labels its rooms; map the green/blue/red doors mentally before spending any swipe.
  3. Green modules first. A green door is usually one card + a fuse for lab crates — and sometimes a blue card pickup, same as surface greens.
  4. Blue modules. The common verified pattern: green card to reach the fuse box, fuse in, then the blue reader. Military crates and lab loot inside.
  5. Red modules — the payday. Red rooms want a red card and 1–2 fuses depending on the module; the richest variant pays 3 elite crates plus large crates. Timers here are short — fuse, flip, and move without detours.
  6. Sweep and resupply. Between card rooms, labs are dense with food, med, and tech scatter — top up as you clear.

After the run

Loot goes home by sub — leave the moonpool the way you came and watch for campers at your dock village. On a good station, a repeat dive next restock is absolutely worth the fuel.

Underwater Labs — quick answers

How many fuses should I bring to Underwater Labs?
2–3 per dive. Module circuits run on short timers, and a missed timer burns the fuse — spares keep a long dive from dying at the last door.
What cards do Underwater Labs need?
All tiers appear across the modules: green rooms are a card and a fuse; blue modules commonly want green + blue cards + a fuse; red modules want a red card and 1–2 fuses. The exact mix varies because every lab is procedurally assembled.
How do I get to Underwater Labs?
Solo or duo submarines from fishing villages are the standard way in — dock at the lab's moonpool. Committed divers can make it with tanks and flippers on shallow stations.
Is the loot worth it?
A full station chain commonly pays 500–2,000 scrap plus elite-crate gear, with less player competition than any comparable surface monument.