- What to know
- Quick overview of the Tadpole Depth Module
- Where the Tadpole Depth Module mission starts
- The exact direction you need to travel
- The dangerous cave where the module is hidden
- How to get the module inside the crashed Tadpole
- What the Tadpole Depth Module actually does
- Crafting requirements for the Depth Module MK.1
- Common mistakes players make during this mission
- Why this upgrade is one of the biggest progression gates
What to know
- The Tadpole Depth Module MK.1 increases your Tadpole crush depth from 250m to 450m.
- You first need access to the Alien Ruins and a working battery to reveal the module location.
- The module blueprint is hidden inside a crashed Tadpole in a deep Needler-infested cave.
- No scanning is required — simply collect the data box to unlock the upgrade.
The Tadpole Depth Module MK.1 is one of the most important vehicle upgrades in Subnautica 2. Without it, your Tadpole submarine starts taking crush damage below 250 meters, which blocks access to several deeper biomes, upgrade materials, and story areas. Fortunately, the module can be obtained fairly early once you reach the Alien Ruins region.
Quick overview of the Tadpole Depth Module
| Feature | Details |
|---|---|
| Upgrade Name | Tadpole Depth Module MK.1 |
| Effect | Increases crush depth to 450m |
| Location | Deep cave southeast of Alien Ruins |
| Required Vehicle | Tadpole |
| Blueprint Unlock | Data box pickup |
| Scanning Needed | No |
| Danger Level | Moderate to High |
| Main Threats | Needler fish / deep-water predators |
Where the Tadpole Depth Module mission starts
To begin the hunt for the upgrade, head to the Alien Ruins Research Base area. This is also the same location where players usually obtain the Engine Efficiency module. Inside the ruins, you will find a NOA/Knower console that reveals the location of the crashed Tadpole carrying the Depth Module blueprint.
You must insert a battery into the console before interacting with it. If you arrive without one, there is usually a spare battery located in the opposite room nearby. Once powered, the terminal provides a navigation clue pointing you toward the module location.
The exact direction you need to travel
After leaving the Alien Ruins, travel southeast at roughly 165 degrees. This direction is important because the cave entrance is not clearly marked and can be easy to miss among the terrain.
The route is also close to the same general area used for locating parts of the Improved Fin upgrade, so experienced explorers may already recognize the region.
As you move farther from the ruins, you will eventually encounter a deeper trench system populated by hostile Needler creatures. This is the correct area.
The Tadpole Depth Module is located inside a submerged cave filled with aggressive Needler fish and deeper environmental hazards. The cave itself extends below the Tadpole’s default 250m crush depth, which means your vehicle will begin taking damage if you stay too deep for too long without the upgrade already installed.
Because of this, preparation matters.
Recommended preparation before entering
| Recommended Item | Why You Need It |
|---|---|
| Repair Tool | Fix crush damage quickly |
| Extra Power Cell | Long travel distance |
| Spare Oxygen | Emergency backup |
| Medkits | Wildlife attacks |
| Seaglide/Wakemaker | Faster escape option |
The safest strategy is to park your Tadpole just above the cave entrance and continue downward manually for the final section. This minimizes crush damage and reduces the chance of predators destroying your vehicle while unattended.
How to get the module inside the crashed Tadpole
Once inside the cave, continue descending until you locate a crashed Tadpole submarine resting near the bottom of the area. Nearby wildlife may patrol aggressively, so avoid lingering in open water for too long.
Inside or near the wrecked vehicle, you will find a data box/container containing the Tadpole Depth Module MK.1 blueprint.
Unlike many other vehicle upgrades in the game, you do not need to scan fragments. Simply picking up the data box instantly unlocks the crafting recipe.
What the Tadpole Depth Module actually does
The default Tadpole vehicle can only safely operate down to 250 meters before hull pressure starts damaging the submarine. The Depth Module MK.1 extends that limit to 450 meters, allowing you to safely explore deeper biomes, hidden facilities, and progression areas.
This upgrade is effectively mandatory for mid-game exploration because many advanced crafting materials and story locations are deeper than the base vehicle limit.
Here is the upgrade effect in formula form:
Crafting requirements for the Depth Module MK.1
After unlocking the blueprint, you can craft the module at the Modification Station.
| Material | Quantity |
|---|---|
| Celestine | 3 |
| Enameled Glass | 2 |
| System Chip | 1 |
Celestine is generally the hardest material to obtain because it appears deeper near hostile regions around the Alien Ruins biome.
Common mistakes players make during this mission
Driving too deep too early
Many players continue piloting the Tadpole directly into the cave until the hull begins collapsing. The safer approach is stopping near the entrance and diving manually.
Forgetting a repair tool
Since the cave exceeds 250m depth, crush damage happens quickly. Without repairs, the Tadpole can be destroyed before you escape.
Missing the data box
The blueprint is not obtained through scanning. Some players waste time searching for fragments instead of opening the container inside the crashed vehicle.
Why this upgrade is one of the biggest progression gates
The Tadpole Depth Module is essentially your ticket into the deeper parts of the game. Once installed, exploration becomes far safer and several advanced zones become accessible without constant hull warnings.
It also opens the path toward rarer materials, advanced upgrades, and additional late-game Tadpole modules such as improved efficiency systems and advanced chassis upgrades.
The Tadpole Depth Module MK.1 is one of the most impactful upgrades you can unlock in the early-to-mid game of Subnautica 2. The process is relatively straightforward once you know where to go, but the surrounding cave system can easily destroy an unprepared vehicle.
Bring repair supplies, follow the 165-degree heading from the Alien Ruins, and grab the data box from the crashed Tadpole to permanently unlock deeper ocean exploration.
