How to get a Subnautica 2 tadpole and the tadpole pens key code
To get the tadpole pens key code in Subnautica 2, you need the tadpole vehicle itself, so here's a full guide to both
The Subnautica 2 tadpole is an underwater vehicle that makes exploration easier and faster, and allows you to reach greater depths while making its own oxygen. To do anything, like obtain resources or scan items, you do have to leave the tadpole, but at least you'll be doing so with a full tank of air, even 250m below the surface.
What makes Subnautica 2 so terrifying is the constant threat of drowning or being eaten by a deadly leviathan. Some of that is taken away when you're inside a tadpole (though me and my tadpole were eaten whole on the outskirts of the world, so the threat is still very real), but you cannot progress the story or reach certain areas - including the Subnautica 2 tadpole pens - without one. So, here's how to get one, and how to use it to get the tadpole pens key code.
How to get a Subnautica 2 tadpole
To get the Subnautica 2 tadpole, you need to scan three tadpole fragments and build a moonpool and a vehicle fabricator at your base. There are tadpole fragments all over, but here are some of the best locations:
- Near Ruby's Black Box, 350m northeast of lifepod
- 145m south of lifepod, 90m below
- Inside the Colonist Bunker, 400m southwest of lifepod, 88m below
With your tadpole blueprint unlocked, use your Subnautica 2 Habitat Builder tool to place a vehicle fabricator and a moonpool, which you must also have unlocked by scanning their fragments.
A vehicle fabricator must be placed on the edge of a moonpool, but the moonpool must be wide enough to house the vehicle fabricator. For some reason, you can place a smaller moonpool than is required, so if you're having trouble placing the fabricator, try deconstructing your moonpool and placing it in a bigger room, ensuring it's full-sized, then place your vehicle fabricator.
How to get the Subnautica 2 tadpole pens key code
If you've made it as far as the tadpole pens already, you're here in search of the tadpole pens key code, which lets you through to a room at the back of the structure. Once you've explored the tadpole pens for the first time, your NoA should soon ping you the location of Zip's black box, which holds the key code.
This is a tough location to get to, and you'll need both the Subnautica 2 Rebreather and your tadpole to get there, as well as the heat tolerance adaptation. Head over to the rough location of Zip's black box, as marked on your screen, and then start spiralling slowly down using descending pathways in the nearby area. While you can't descend straight down to the marker, the area is pretty good at guiding you down naturally.
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Eventually you should be able to see the cave entrance in the image above, which is marked roughly by Zip's black box marker, but you won't see the black box itself. This is telling you to go into the cave, where you'll first find Gram's black box. Don't get distracted, as you'll need to head deeper into the cave to find Zip's. Interact with the black box, and the key code will automatically be saved to your PDA - there's no actual code.
You will need to leave your tadpole at this point, so make sure you've got your Rebreather equipped since you're in pretty deep here.
Head back to the tadpole pens and press the button in front of the locked door. With Zip's black box data downloaded to your PDA, the door will now open, and you can head inside to discover the next part of the mysterious story.
Your tadpole will also help you navigate through the depths of the Zezura Desert, for which you'll also need to have discovered the heat tolerance adaptation, and cleared bloom cankers with your Sonic Resonator. I'll be able to help you with all of that with our incoming guides.
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After studying Music and Lifestyle journalism and writing a column for a stylish lifestyle magazine in her hometown of Brighton, Danielle finally found her feet writing about videogames for WePC in 2021. She then honed her guides writing skills at PCGamesN between 2022 and 2026, when she took those skills to GamesRadar as a Guides Writer. Danielle's guides are a safe space - she definitely got stuck before you did, which is why she's perfect for the job. When she's not replaying the Silent Hill games or a more up-to-date single-player horror game, you'll find her fighting for her life in Dead by Daylight, tending to a garden in Stardew Valley, or doing both in Minecraft.
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