Upgrading the Tadpole

Build the Tadpole first. Everything past the 100 m line wants vehicle support, and the Tadpole is the answer to "how do I go deeper."

Tadpole modules

Module	Type	What it does
Tadpole	Core vehicle	The base module. Mobility and manipulation. Required before any chassis.
Scout Ray Chassis	Speed chassis	Max swim acceleration 1600. Speed Boost effect granted. Use for scouting and long-distance travel.
Tadpole Haul Chassis	Cargo chassis	Max swim acceleration 250. Camera switch ability. 30-slot built-in cargo plus a second hardpoint.
Tadpole Depth Module Mk. 1	Depth upgrade	Required for full exploration of the Graveyard (10-315 m) and the Observatory (4-337 m).
Tadpole Depth Module Mk. 2	Depth upgrade	Required for the Power Plant (99-470 m) and Root Canyons (191-476 m).

Pick a chassis

The two chassis are genuinely different vehicles once attached.

• Scout Ray is six times faster than Haul Rig at the top end: 1600 vs 250 max swim acceleration. It also grants a Speed Boost effect on top of the raw acceleration. Use it when you're going somewhere on purpose and don't need to bring much back.

• Haul Rig has 30 slots of built-in cargo plus a second hardpoint that can hold additional storage. Total capacity of up to 4 passengers in co-op. Use it for resource runs to known biomes or for ferrying co-op partners.

You can swap chassis by undocking and redocking at a Tadpole Dock. The Tadpole itself stays. Pick the chassis for the trip you're about to take, then swap when you come back.

Crafting recipes

The Tadpole and both chassis are built at a Vehicle Fabricator. Depth modules are crafted at a Modification Station.

What it costs

Item	Station	Materials
Tadpole	Vehicle Fabricator	2x Titanium Ingot, 1x Glass, 1x System Chip, 1x Power Cell
Scout Ray Chassis	Vehicle Fabricator	2x Plasteel Ingot, 1x Advanced Wiring Kit, 1x Dedicated Core, 1x Strong Acid
Tadpole Haul Chassis	Vehicle Fabricator	4x Titanium Ingot, 3x Strontium, 3x Enameled Glass, 1x Dedicated Core
Depth Module Mk. 1	Modification Station	3x Celestine, 2x Enameled Glass, 1x System Chip
Depth Module Mk. 2	Modification Station	2x Dedicated Core, 2x Troilite, 2x Mangalloy Ingot

The Tadpole core is the cheapest piece. The Scout Ray needs Strong Acid and a Dedicated Core, which are mid-game materials. The Haul Rig is the most Titanium-hungry at 4 Ingots. Both depth modules need materials from deeper biomes, so each one funds the trip to get the next.

Depth gates

The Rebreather covers you down to about 130 m without vehicle support. The Mk. 1 opens everything down to about 340 m. The Mk. 2 goes to about 480 m. For what to mine at each tier, see How to find resources.

Build order

Build the Scout Ray first. The early game punishes slow travel. You'll spend more time going to and from things than doing anything else, and speed compounds. Once your base economy is stable and you're hauling specific resources from known biomes, swap to the Haul Rig.

Missing fragments?

Two checks.

1. Are you scanning every biome you can reach? Fragment locations are fixed, not randomized. Cycling through different surface biomes usually turns up what a single biome can't.

2. Have you advanced the story? Some blueprints unlock through story progression rather than scanning. Picking up all the raw materials for a recipe can also auto-unlock it.