The Seatruck is Subnautica: Below Zero’s signature vehicle — a modular submarine that can be customised with different function modules to serve as a transport, a mobile workshop, or even a home away from home. Unlike the Seamoth from the original Subnautica (which is compact and fast but offers no interior space) or the Cyclops (which is enormous and slow), the Seatruck strikes a balance: it has a small interior, can dock modules for additional functionality, and is manoeuvrable enough for exploration without being painfully slow. This guide covers everything you need to know about the Seatruck.
Building Your First Seatruck
The Seatruck blueprint is obtained from fragments in the early exploration areas — similar to the Seamoth in the original Subnautica. Finding and scanning the fragments is a high priority in the first hours of play. Once you have the blueprint, the Seatruck requires Enameled Glass, Lead, Titanium Ingots, and Lubricant — reasonably accessible early-game materials. Build it in a Moonpool.
The base Seatruck without any modules is small — just the cab unit. You sit in the front, can look out, and operate the vehicle. It has its own oxygen supply, providing air for as long as the vehicle is powered. Without modules, it functions as a fast personal submarine for solo exploration and resource transport.
Seatruck Modules and What They Do
| Module | Function | When to Build |
|---|---|---|
| Aquarium Module | Houses live fish for food supply, Bioreactor fuel | When you need a mobile food source |
| Docking Module | Allows a Prawn Suit to dock to the Seatruck | Before entering Prawn-required areas |
| Fabricator Module | Includes a Fabricator for mid-mission crafting | Mid-game for extended exploration |
| Sleeper Module | Contains a bed for time skip and health recovery | For long exploration missions |
| Storage Module | Large cargo space, 4×4 grid | Whenever you need to haul more than the cab holds |
| Teleportation Module | Late-game module for quick traversal | End-game locations |
Seatruck Upgrades
Beyond modules, the Seatruck itself can be upgraded at the Vehicle Upgrade Console in a Moonpool. The most important upgrades are: Depth Module (extends maximum operating depth, essential for reaching later story locations), Hull Reinforcement (increases integrity against creature attacks), Engine Efficiency (reduces power consumption, extending range), and Perimeter Defence (electric deterrent that damages attacking creatures and breaks Chelicerate grabs).
Seatruck vs Prawn Suit: Knowing When to Switch
The Seatruck handles ocean travel. The Prawn Suit handles deep terrain that requires precise mobility — underwater cliff faces, cave systems too narrow for a full sub, and areas with significant creature threat at close range. The Prawn Suit’s grappling arm and drill arm make it invaluable for specific tasks. The Docking Module allows you to bring both on a single mission, switching between them as needed. This combination is the standard end-game exploration setup in Below Zero.
Seatruck Tips and Tricks
- The Seatruck auto-navigates in a straight line when you hold the throttle and release the wheel — useful for planning a route while looking at your map
- Modules add drag and reduce speed — remove modules you do not need for specific missions
- The Seatruck can enter very tight spaces compared to the original Cyclops — take advantage of this in cave systems
- Recharge your Seatruck power cells at your base before long exploration missions — running out of power leaves you in complete darkness
- The sonar module helps with navigation in dark or murky deep ocean areas
Seatruck Coverage on RicardoPlays
Ricardo’s Below Zero series on the RicardoPlays channel covers the full Seatruck progression — from the first build to the fully-modded end-game configuration. The channel includes module setup guides and a breakdown of which upgrade order is most efficient for story progression. Watch the Seatruck-focused episodes for a visual guide to the vehicle’s full potential.