Last updated: 5 September 2026

Subnautica 2 Vehicles Guide — Tadpole, Chassis & Depth Modules

Swimming gets you through the early game; the Tadpole submersible gets you through everything else. A vehicle fundamentally changes Subnautica 2: it acts as a moving oxygen supply, absorbs creature attacks that would end your dive, and carries resources back to base even when your personal inventory is full. The Tadpole is modular — three chassis variants reshape how it handles entirely, and a set of upgrade modules let you push it into biomes that would crush the bare hull in seconds. This guide covers the whole process, from your first Moonpool to choosing the right configuration for deep-water exploration.

01When to Build Your First Vehicle — and the Moonpool Requirement

The Tadpole becomes available once you've established a base with a Moonpool. The Moonpool is a specialised base module that sits below a habitat room and provides an underwater docking bay. It serves three purposes: it houses the Vehicle Fabricator (the station where vehicles are built), it charges docked Power Cells automatically while the vehicle is parked, and it lets you swim directly in and out of your base without going through a hatch.

You don't need a vehicle in the first hour — the Seaglide handles the shallow starting biome comfortably. The tipping point comes when you want to push below 100 metres consistently, run long-distance resource routes, or bring multiple players along to carry materials. That's when building a Moonpool starts paying for itself.

• Build the Moonpool using your Habitat Builder — it attaches to the underside of a compatible room module.
• Inside the Moonpool structure you'll find the Vehicle Fabricator. This is entirely separate from the basic Fabricator in your escape pod — it is the only place where vehicle blueprints can be crafted.
• There is no separate console for installing upgrades — you craft modules at a Modification Station (built with the Habitat Builder, materials-gated behind a Research Outpost scan) and then slot them straight into the Tadpole's own upgrade hatch on its hull.
• Build a Tadpole Dock adjacent to the Moonpool to park the vehicle inside your base with its chassis attached, keeping it charged and ready.

02How to Unlock and Craft the Tadpole

The Vehicle Fabricator will not show you the Tadpole recipe until you have scanned at least three Tadpole fragments. These appear in wrecks, sunken debris fields, and cave systems scattered across the ocean floor. Approach each one and hold the scan button — on the third scan the full vehicle blueprint unlocks.

With the blueprint active, head to the Vehicle Fabricator inside your Moonpool and craft the Tadpole. The materials are mid-game accessible: 2× Titanium Ingots, 1× Glass, 1× System Chip, and 1× Power Cell. The vehicle appears directly in the Moonpool docking bay, ready to board.

• Titanium Ingots are smelted from standard Titanium at a Fabricator — check the recipe if you haven't made them before.
• System Chip is crafted at a Fabricator from 1× Wiring Kit and 2× Quartz — you'll be making these for base upgrades anyway.
• Power Cell is crafted at a Fabricator from 2× Basic Battery, 1× Strong Acid, and 1× Salt.
• These material costs reflect the September 2026 Early Access build. EA games can adjust recipes in updates — cross-check your in-game PDA if something looks different.

The default Tadpole has a top speed of 8 m/s, one pilot seat, four upgrade module slots, one hardpoint for external storage, and a base crush depth of 250 metres. Below that depth, the hull takes progressive damage.

03Chassis Variants — Scout Ray, Haul, and Seafrog

The Tadpole's chassis is swappable at the Moonpool. Each chassis physically reconfigures the submersible and rewrites its handling — you do not build a new vehicle, you slot in a different chassis. All chassis variants share the Tadpole's four upgrade module slots.

Scout Ray Chassis — the speed build. Raises top speed to 10 m/s and maximises acceleration and turn rate. This is the choice for solo exploration in high-threat biomes where quick manoeuvring matters and escaping a Leviathan encounter is a realistic concern. The blueprint comes from a single scan, not fragments: it's attached to a docked Tadpole inside the Tadpole Pens, a landmark in the shallow Graveyard biome roughly 150 m down. The area's heat means you'll need the Heat Tolerance adaptation before you can reach it safely. Once scanned, build it at the Vehicle Fabricator from 2× Plasteel Ingot, 1× Advanced Wiring Kit, 1× Dedicated Core, and 1× Strong Acid.

Haul Chassis — the cargo build. Attaches catamaran-style cargo pods along both hull sides, reducing acceleration sharply (slowest of the three configurations) but expanding seating to four players. Built for co-op resource ferry runs — the slower speed doesn't matter when the goal is carrying a full load safely back to base. Haul chassis fragments are found at alien ruins approximately 1,300 metres east of the lifepod. Blueprint requires 4× Titanium Ingots, 3× Strontium, 3× Enameled Glass, and 1× Dedicated Core.

Seafrog Chassis — the walker build. Converts the Tadpole into an exosuit-style submersible capable of walking along the seafloor and entering narrow spaces too small for the standard hull. Confirmed by Unknown Worlds as part of the vehicle roadmap but not yet available in survival mode as of the September 2026 Early Access build — it is slated for a future update.

• Only one chassis can be installed at a time — they don't stack.
• The base Tadpole (no chassis) is a solid middle ground at 8 m/s with standard acceleration. Use it while you hunt for chassis fragments.
• Chassis do not occupy upgrade module slots — your four slots remain fully available regardless of which chassis you use.

04Depth Modules — Unlocking Deeper Biomes

The most critical upgrade you'll install is the Depth Module Mk.1. Below the base Tadpole's 250-metre crush depth, the hull takes continuous pressure damage that will destroy the vehicle and everything aboard if you don't ascend. The Mk.1 extends the safe limit to 450 metres, opening up the Needler Nest structure and the deeper fringes of the Graveyard biome.

The Mk.1 blueprint (a Recipe Data Card) is found near a crashed Tadpole inside the Needler Nest — a landmark structure roughly 300 m down in the Overgrown Ruins, not a biome in its own right. Take the base Tadpole as deep as you safely can, then swim the rest on foot to retrieve it. Once scanned, craft it at a Modification Station using 3× Celestine, 2× Enameled Glass, and 1× System Chip, then install it directly into the Tadpole's own upgrade hatch on its hull.

The Depth Module Mk.2 extends the crush depth further to 800 metres, unlocking the deepest biomes including the Abyssal Trench (confirmed to reach 500 m and beyond). As of the September 2026 Early Access build, Mk.2 is available in Creative Mode only — there is no Recipe Data Card for it anywhere in the survival-mode world, so it cannot yet be crafted or installed there. Expect it in a future EA content update.

• The crush-depth warning sounds 20 seconds before damage begins — ascend immediately on hearing it, don't grab one more resource first.
• Crush damage is continuous once you breach the limit and ramps up fast. A few seconds at 260 m is survivable; 30 seconds at depth will destroy the vehicle.
• Mk.1 and Mk.2 do not stack — Mk.2 replaces Mk.1 in the same upgrade slot when it becomes available.
• Each depth module uses one of the Tadpole's four upgrade slots, leaving three for the upgrades below.

05Other Upgrade Modules Worth Prioritising

Beyond depth modules, four upgrades make meaningful differences in how the Tadpole performs day to day. Craft them at a Modification Station (built with the Habitat Builder, its own blueprint unlocked by scanning one at the Research Outpost) and install them directly into the Tadpole's own upgrade hatch — there's no separate console.

• Engine Efficiency — reduces power consumption by 20% per installed module and stacks up to four times (80% total reduction). Two or three modules is the practical target, freeing remaining slots for other upgrades. Blueprint: Research Outpost (Recipe Data Card, ~140 m). Materials: 2× Titanium Ingot, 2× Glass, 1× System Chip.
• Cavitation Muffler — reduces engine noise, narrowing the detection range of Leviathan-class creatures patrolling deeper biomes. Prioritise this before pushing into the Needler Nest or Graveyard. Blueprint: Karakorum Metal Farms (southwest worksite).
• Strike Armor — reduces incoming physical damage by 50%. Combined with the Cavitation Muffler, it forms the core defensive package for high-threat zones. Blueprint: a worksite near the Research Outpost (Recipe Data Card, ~195 m). Materials: 2× Enameled Glass, 2× Strontium.
• Photovoltaic Charger — recharges the Power Cell using solar input while the Tadpole is within 40 metres of the surface during daylight. Unknown Worlds hasn't published an exact charge rate, so treat any specific per-hour figure you see elsewhere as unofficial. Lower priority than defensive modules but useful if you spend time in shallow biomes and want free passive top-ups.

Recommended slot priority for most playthroughs: Depth Module Mk.1 → Engine Efficiency ×2 → Cavitation Muffler. This fills all four slots with the highest-impact upgrades in order of when you'll need them. In high-threat biomes where Leviathans are frequent, swap one Engine Efficiency slot for Strike Armor.

06Upcoming Vehicles — PRAWN Suit and Trident

The Tadpole is still the only craftable vehicle as of the September 2026 Early Access build. Unknown Worlds has confirmed two additional vehicles for future updates:

PRAWN Suit — a mech-style exosuit returning from the original Subnautica, redesigned for Subnautica 2 with co-op-oriented changes and integration with the game's DNA modification system. Originally expected around EA Update 1.1, the PRAWN Suit did not ship with the Adaptive Measures update (July 8, 2026). It also wasn't part of the Buddy System update (1.2, August 19, 2026), which focused on co-op features like proximity chat and revives rather than new vehicles. As of that update's September 1, 2026 hotfix, Unknown Worlds still has not confirmed a new target date.

Trident — the spiritual successor to the original Subnautica's Cyclops, planned as a multi-crew submarine that can dock smaller vehicles internally and serve as a mobile base. It was confirmed at the Subnautica 2 Pre-Launch Showcase on May 9, 2026 (some community coverage calls this the "First Dive Showcase," but that's not the event's official name). The Trident cannot be built in survival mode in the current EA build, and Unknown Worlds has not given a target update or date.

• The Seafrog chassis (Tadpole walker variant) is also confirmed but unavailable in survival mode as of the September 2026 build — it is a separate addition from the PRAWN Suit.
• Recipe details for both the PRAWN Suit and Trident have not been finalised — check the PDA and in-game notice board once the updates drop.
• Unknown Worlds' public roadmap groups the PRAWN Suit, Trident, and a new region around the Collector Leviathan into a larger future expansion, without committing to a date.