Underground building, not a promo item
How to get a Build Kit in AETHUS
One community article says to build an Expedition Hub on the surface, craft an Empty Buildkit, then press B underground and select the subterranean tab. Its normal recipe is 5 Building Material + 1 Tangrite Bar, reduced to 3 Building Material with a Manufacturing Hub. Euchale explicitly explains the Manufacturing Hub discount notation; the wiki repeats it, so independence is not established.
The earlier Steam guide used the shorthand 5/3 Building Material. The readable wiki explains it as 5 normally and 3 with a Manufacturing Hub. Euchale explicitly explains the discount notation; it is not an unresolved choice between two unrelated recipes.
Recipe and variants
The earlier guide records 5/3 Building Material + 1 Tangrite Bar. The linked wiki explains 5 normally and 3 with a Manufacturing Hub; Euchale explicitly labels parenthesized values as the Manufacturing Hub cost. The same table lists Lightstick, Large Crate, Power Relay, Coolant Hypercompressor, AtmoDome, and AtmoDome (RadProtect Edition) as kit variants. The Expedition Hub unlock cost (Advanced Electronics, a Servomotor, Calorite bars, Reinforced Building Material) is only in one walkthrough.
If placement fails
Press B to open build mode. V cycles snap points on multi-door pieces (patch 1.025). Hold Shift to turn snap off (patch 1.026). Devistater's Seam X-5 guide is the concrete case: if the relay is unpowered, the far side will not accept oxygen or cooling hardware. That is a power problem, not a missing recipe.
Questions
Why will the Build Kit not place?
Check the Expedition Hub, that a kit is in your inventory, that the pad has power, and that you are on the underground tab with B. A blocked footprint fails the same way.
Is "buildkit" a separate item from Empty Buildkit?
Searches for buildkit land on the Empty Buildkit recipe. The placed variants are the Lightstick, crate, relay, and dome kits in the same table.
Related
Sources
- Steam News API — Readable 2026-10-28. One originating publisher source; official patch/announcement text, not independent corroboration.
- Build Kit community article — Readable 2026-10-28; Single source for Expedition Hub unlock; discount also explained by Euchale.
- Euchale crafting guide — Empty Buildkit recipe and six variants.
- Steam news 1.025 and 1.026 — V snap points and Shift to disable snap.
- SafeGamerHaven chapter — Chapter titled Crafting BuildKit.
Last checked: 2026-10-28. Send corrections to [email protected].