Unlock Tadpole Vehicle & Upgrades in Subnautica

Updated 13 November 2026 · Standard formula, shown below

This guide explains how to unlock the Tadpole, a compact one-person vehicle added in the Subnautica 2.0 update, along with its full upgrade tree. You’ll need to have repaired the Aurora’s drive core and crafted a standard Seamoth before the Tadpole’s blueprint becomes available. By the end, you’ll know exactly where to find the fragments, what materials to gather, and how to install every upgrade.

What You’ll Need

A repaired Aurora (drive core fixed)
Seamoth blueprint already unlocked
Laser Cutter (for some wrecks)
Repair Tool (for the Aurora’s drive core)
Scanner (to scan fragments)
Fabricator and Vehicle Upgrade Console (for upgrades)
Materials: Titanium, Lead, Lubricant, and later Rubies, Magnetite, and Plasteel Ingots

Step-by-Step

Step 1: Repair the Aurora’s Drive Core

Before any of the new vehicles appear, you must repair the Aurora’s drive core. This requires a Radiation Suit (to survive the area), a Repair Tool, and a Laser Cutter to access certain rooms. Once inside the drive room, use your Repair Tool on the three damaged panels. This triggers the ‘new vehicles’ event in the game’s data.

Step 2: Build a Seamoth (Required Pre-Requisite)

The Tadpole’s blueprint is only offered after you’ve crafted a Seamoth at least once. Build the Mobile Vehicle Bay, then craft a Seamoth with the standard materials (Titanium Ingot, Lead, Power Cell, Lubricant, Glass). Launch it into the water. This step unlocks the ability to find Tadpole fragments.

Step 3: Scan Three Tadpole Fragments

With the Seamoth built, Tadpole fragments will now spawn in specific wrecks. You need to scan three distinct fragments to unlock the blueprint. The most reliable locations are:

Grassy Plateaus wreck (around 200m depth) – check the broken hull sections.
Mushroom Forest wreck (near the northern Blood Kelp zone) – look inside the large cave.
Underwater Islands wreck (southwest of the Aurora) – on the upper deck.

Use your Seamoth to reach these, but be ready to exit and scan with your handheld scanner. Each fragment gives 33% progress.

Step 4: Craft the Tadpole at the Mobile Vehicle Bay

Once all three fragments are scanned, the Tadpole blueprint appears in your Mobile Vehicle Bay. It costs:

1x Titanium Ingot
1x Lead
1x Power Cell
1x Lubricant
1x Glass

Deploy the Mobile Vehicle Bay on flat water, approach the hologram, and select ‘Craft Tadpole’. It will build in about 10 seconds.

Step 5: Build the Vehicle Upgrade Console

To install any upgrades, you need a Vehicle Upgrade Console in your Moonpool or on a Cyclops. If you haven’t built one, craft it at a Fabricator using: 1x Titanium Ingot, 1x Computer Chip, 1x Quartz. Place it in the Moonpool’s upgrade panel slot.

Step 6: Craft and Install Tadpole Upgrades

The Tadpole has four upgrade slots. Each upgrade is crafted at the Vehicle Upgrade Console. Here are the available upgrades and their effects:

Hull Reinforcement – reduces collision damage. Costs: 3x Plasteel Ingot, 1x Diamond.
Storage Module – adds 4 extra inventory slots. Costs: 1x Titanium, 1x Lithium.
Depth Module MK1 – increases crush depth from 200m to 300m. Costs: 1x Plasteel Ingot, 1x Magnetite.
Depth Module MK2 – increases crush depth to 400m. Requires MK1. Costs: 1x Plasteel Ingot, 2x Rubies.
Depth Module MK3 – increases crush depth to 500m. Requires MK2. Costs: 1x Plasteel Ingot, 3x Kyanite (found in the Lava Zones).
Sonar Upgrade – reveals terrain and creatures. Costs: 1x Advanced Wiring Kit, 1x Magnetite.
Perimeter Defense System – emits an electric shock to deter leviathans. Costs: 1x Wiring Kit, 1x Battery, 1x Copper Wire.

Step 7: Install the Upgrades

Approach the Tadpole while it’s docked in the Moonpool or parked near the Cyclops upgrade panel. Open the upgrade panel (press E on the vehicle’s side), then drag the crafted upgrade from your inventory into an empty slot. The upgrade is instantly applied.

Common Mistakes

Scanning fragments before repairing the Aurora – the fragments simply won’t spawn, so you’ll waste time searching.
Not building a Seamoth first – the game checks for a Seamoth in your save data. If you’ve never built one, the Tadpole fragments remain invisible.
Scanning the same fragment twice – each fragment only gives one scan. You need three distinct ones.
Forgetting the Depth Module MK1 before MK2 – you cannot skip tiers; each higher module requires the previous one in your inventory.
Using the wrong console – upgrades are crafted at the Vehicle Upgrade Console, not the standard Fabricator.

Tips

Use the Seamoth’s sonar (if you have it) to spot wrecks more easily while fragment hunting.
Bring a spare battery and a laser cutter to the wrecks – some fragments are behind sealed doors.
Park your Seamoth near the wreck’s entrance so you can retreat quickly if a predator shows up.
Depth Module MK3 is essential for exploring the Lost River and Lava Zones, but you’ll need a Prawn Suit for the deepest areas anyway.
If you’re low on Rubies, check the Grand Reef and the Blood Kelp Trench – they spawn in clusters.

Troubleshooting

I’ve repaired the Aurora and built a Seamoth, but no fragments appear. This can happen if you’re in an older save that predates the 2.0 update. Try saving and reloading the game, then re-check the wrecks. If they still don’t appear, verify that you’ve actually crafted (not just unlocked) the Seamoth – the game tracks the crafted item.

I scanned three fragments but the blueprint didn’t unlock. Make sure you scanned the correct type – there are other fragments in the game (like the Cyclops or Prawn) that look similar. Check your PDA’s ‘Blueprints’ tab to see your progress on ‘Tadpole’. If it shows 2/3, you missed one.

I can’t craft the Depth Module MK2 because it says ‘requires MK1’. You must have the MK1 module in your inventory (not just installed on the vehicle). Craft it, keep it in your inventory, then craft MK2.

The Tadpole won’t dock in my Moonpool. The Tadpole is smaller than the Seamoth, so it fits any Moonpool. If it won’t dock, make sure you’re approaching slowly and centered. If it’s stuck, try deconstructing and rebuilding the Moonpool.

My Tadpole is taking damage at 250m even with MK1 installed. Check that the upgrade is actually installed (open the upgrade panel). Sometimes the game doesn’t auto-equip. Also, MK1 only goes to 300m – at 300m it will start taking damage.

Frequently Asked Questions

Is the Tadpole better than the Seamoth?

The Tadpole is faster and more maneuverable, but has less storage (base 4 slots vs Seamoth’s 6). It also has a lower base crush depth (200m vs 200m for Seamoth), but its upgrades go higher (500m vs 900m for Seamoth). It’s a trade-off – the Tadpole is great for speed, but the Seamoth is better for deep exploration.

Can I use the Tadpole in the Lost River?

With the Depth Module MK3 (500m), you can reach the upper Lost River (around 500m), but the deeper parts (600m+) will crush it. For those, you’ll need a Prawn Suit or Cyclops.

Do I need the Tadpole to finish the game?

No, it’s optional. The Seamoth and Prawn Suit are sufficient for the main story. The Tadpole is a bonus vehicle for players who want speed.

How many upgrade slots does the Tadpole have?

It has four slots, same as the Seamoth. You can mix and match any upgrades, but you can only have one Depth Module at a time.

Can I dock the Tadpole in a Cyclops?

Yes, it fits in the Cyclops’s vehicle bay, but it takes up the same slot as the Seamoth. You can’t have both docked simultaneously.

Where can I find Kyanite for the MK3 depth module?

Kyanite is found in the Inactive Lava Zone and Lava Lakes, usually around 900m-1200m depth. You’ll need a Prawn Suit with a Drill Arm to mine it, or you can pick up loose pieces.

Method: the standard formula for this calculation, rounded as each result states. See how the calculators work or report an error.