Three-card red puzzle with the densest scientist roster in the game (~29 NPCs).
Endgame puzzle monuments. Multi-card progression, scientist NPCs, high radiation, often multiple fuses. Top-tier rewards (elite crates, blueprints, weapons) and the focal points of every late-wipe meta.
| Keycards | 1× Green + 1× Blue + 1× Red |
|---|---|
| Fuses required | 2 |
| Scientists / NPCs | ~29 armed scientists patrolling corridors |
| Radiation | 11+ at entrance, 26+ in deeper sections (full hazmat strongly recommended) |
| Recycler | Yes (×1, on the outside area) |
| Workbench | None on-site |
Military Tunnels is the underground three-card endgame puzzle — green → blue → red progression, ~29 patrolling armed scientists across the corridor network, hazmat-mandatory radiation (11+ at entrance, 26+ in deeper sections), and elite-tier loot scattered across multiple underground levels. The densest scientist roster in the game by a meaningful margin. Best with a duo or trio; soloable but punishing.
Multi-stage three-card progression deep underground:
Total fuses needed: 2. Total scientists in the complex: ~29.
Military Tunnels has the highest scientist density of any single Rust monument — 29 armed NPCs spread across the underground corridor network. To survive:
All three: green + blue + red keycards. Plus 2 electrical fuses for the multi-stage puzzle progression.
Approximately 29 armed scientists patrolling the complex corridor network. The highest single-monument scientist density in the game. They use SMGs and rifles, are aggressive, and respawn over time.
Yes — 11+ at the entrance, 26+ in the deeper sections. Full hazmat is mandatory and even that may not be enough for sustained presence in the deepest areas; bring radiation pills.
Yes, but it's punishing. Bring a Tier 2 rifle, full hazmat, 150+ rounds, multiple medkits, and patience. Duos and trios clear significantly faster and safer.
Yes — one recycler in the outside area, useful for processing components before the trip home. The interior is purely combat and loot.
Military Tunnels represents the full PvE challenge in Rust's monument system. The three-card progression, dense scientist roster (~29 armed NPCs), mandatory hazmat radiation, and underground combat layout combine into the hardest single-monument encounter outside Launch Site and Missile Silo. Clearing it solo is a meaningful achievement; clearing it with a duo or trio is a regular mid-to-late-wipe ritual.
The reward profile justifies the difficulty. Multiple Elite Crates inside the deepest puzzle chamber make a successful Military Tunnels run a wipe-shaping event — the components, blueprints and weapons recovered fund subsequent raids and base upgrades. Combined with the exterior recycler, the loot-to-trip ratio is excellent for groups that can manage the combat.
The scientist AI uses corridor patrols and ambush positions. Learn the spawn points — they're consistent across map seeds — and engage at corners and chokepoints rather than in the open central rooms. The scientist respawn timer means a sufficiently slow clear will re-engage fresh enemies; aim for full sweep time under 8 minutes if possible.
For the rest of the Tier 3 progression, see Launch Site, Arctic Research Base and Missile Silo. Raid math at the Raid Calculator.