The Tadpole is the centerpiece vehicle of SN2 Early Access. Out of the box it safely reaches 250 m, which is barely past the Karakorum lip. The right module loadout decides whether you're stuck farming surface biomes or comfortably running the Karakorum Power Plant. Important note: Depth Module Mk.2 is Creative-mode only in EA v1 — it is not yet obtainable in Survival.
Recipe (Vehicle Crafter): Titanium Ingot ×2 + Glass ×1 + System Chip ×1 + Power Cell ×1. Craft time ~10 s. The four ingredients represent the sub's core systems: Titanium Ingot for the pressure hull, Glass for the viewport, System Chip for on-board electronics, and a Power Cell for energy.
The default Tadpole's safe depth ceiling is 250 m. Beyond that, hull pressure begins to damage the sub. 250 m is enough to scout the Karakorum entrance lip and farm all surface biome resources, but it cannot safely reach the Power Plant, Lithium beds, or any deep Gold/Conduit Crystal pocket.
You unlock the Tadpole by scanning Tadpole fragments in the world. You also need a built Vehicle Crafter (its own scanned-fragment unlock) before you can build the sub itself.
Recipe (Modification Station): Celestine ×3 + Enameled Glass ×2 + System Chip ×1.
What it unlocks: Karakorum Power Plant entry, deep Atacamite veins, the Mk.2 datacard, and the safer Conduit Crystal pockets. This is the "everything opens up" upgrade — you'll spend roughly 5-10 hours of playtime working toward it.
Datacard location: The Needler Nest, next to Ruby's crashed Tadpole — not inside the Power Plant. The Needler Nest is on the way to Karakorum and the Mk.1 datacard is the standard prerequisite for the deeper story beats.
Mining tip: Celestine yields 3 units when broken by hand, versus roughly 2 when broken with the Sonic Resonator. Hand-mining is more efficient here — one of the few resources where the tool actually works against you.
Recipe (Modification Station): Dedicated Core ×2 + Troilite ×2 + Mangalloy Ingot ×2.
What it will unlock (once available in Survival): Deep Karakorum endgame zones beyond 450 m and any future biomes added past 800 m.
Mk.2 does not stack. Craft exactly one — any more is wasted materials.
Bottleneck ingredient: Mangalloy Ingot requires Atacamite (copper chloride, Karakorum 100-400m). Gather Atacamite in bulk on your first deep Karakorum descent so you don't have to make multiple trips when Mk.2 ships.
Stock chassis: default load capacity, default speed. Sufficient for early-mid game solo play.
Tadpole Haul Chassis (Vehicle Crafter): Titanium Ingot ×4 + Strontium ×3 + Enameled Glass ×3 + Dedicated Core ×1. Dramatically expands cargo and passenger capacity at the cost of speed. The right choice for serious base building, multiplayer hauling, or long resource runs.
Scout Ray Chassis (Vehicle Crafter): Plasteel Ingot ×2 + Advanced Wiring Kit ×1 + Dedicated Core ×1 + Strong Acid ×1. Enhances acceleration, top speed, and turning. Built for fast exploration and Leviathan evasion. Blueprint is locked inside the Tadpole Pens (see next section).
Seafrog Chassis: Recipe not yet available in Early Access — coming in a future patch.
The Tadpole Pens is a mid-game story facility approximately 675 m east of the Lifepod at ~150 m depth, near hot caves and volcanic vents. NOA directs you there as part of the main quest. Inside you'll find the Scout Ray Chassis blueprint, the Moonpool Recipe Data Card, and a story-advancing NOA terminal.
There is no numeric code to type in. The access key was held by a colonist named Zip. Find Zip's Black Box in a Hot Cave 200-300 m southwest of the facility at 310 m depth. Interact with it — the code saves automatically to your PDA. Return to the locked door, press the button, it opens.
Prepare before going:
All upgrades crafted at the Modification Station and slotted into the Tadpole:
Built with the Habitat Builder: Titanium Ingot ×2 + Silver Ingot ×1 + Copper Wire ×2. Park the Tadpole inside a powered base and the Power Cell recharges automatically — no manual swapping. This is the primary recharge method; the Photovoltaic Charger is a daytime supplement only.
