40 on Steam. One you can miss.

AETHUS achievements

Steam lists 40 achievements: 19 with public descriptions and 21 hidden. The only one the 100% guide calls missable is Vegetarian: do not eat meat or fish. Prepared rations and stew count against it. Difficulty does not lock achievements, according to that same guide alone.

All 40 names, hidden flags and unlock conditions were read from the public Steam achievement page, including its embedded page data. The community completion guide by Leyren repeats the 40 milestones and adds its own collection advice; both were readable during this review. No unlock percentages are frozen here.

Visible achievements

Steam public page data, checked 2026-10-28. Leyren’s independently authored completion guide repeats these milestones.

Achievement names and paraphrased conditions; Steam and Leyren, 2026-10-28.
Name	Unlock condition
Rookie Miner	Mine 50 Mining Nodes
Fledgling Miner	Mine 200 Mining Nodes
Burgeoning Miner	Mine 500 Mining Nodes
Professional Miner	Mine 1000 Mining Nodes
Crafty	Make 50 Items
Good Intentions	Finish the Prologue.
Groundbreaking	Build your first Habitat.
Strike the Earth	Reach the Outer Caverns for the first time.
Explosive Entrance	Clear the Rockfall in the Outer Caverns.
Engineer	Make 200 Items.
Mass Production	Make 500 Items.
Hobby Chef	Prepare 50 items.
Keen Cook	Prepare 200 items.
Chef de Cuisine	Prepare 500 items.
They’ll Be OK, Right?	Deliver the mysterious eggs for the ARC menagerie.
Master Extractor	Reach level V in the Resource Acquisition Partnership Program.
Theme Collector	Find all five megacorp Outpost themes.
Vegetarian	Finish the game without consuming anything made from meat or fish.
They're Limited Edition!	Find all eight variants of Jenkins, the collectable plushy toy.

Hidden achievements

Steam public page data, checked 2026-10-28. Leyren’s independently authored completion guide repeats these milestones.

Show hidden achievement conditions (spoilers)

Achievement names and paraphrased conditions; Steam and Leyren, 2026-10-28.
Name	Unlock condition
Mu-ving On Up	Acquire Lisa Chapman’s keycard from the Mu facility.
Body Engineer	Acquire Dr. Sinclair’s keycard from the Theta facility.
Artificial Unintelligence	Acquire Dr. Harlow’s keycard from the Epsilon facility.
Hero of the Spooky Underground Jungle	Replace the failing reactor at the Lambda facility.
Gift From Above	Reach the Meteorite Crater Facility.
Remote Override	Make the EMP Charge.
Fairytale	Reach the Lost World for the first time.
The Kappa Module	Uncover the truth about Stanley.
Successfully Returned	Bring Stanley to your Outpost and reactivate him.
Getting Warmer	Reach the Magma Rifts for the first time.
Always Something Behind the Waterfall	Find the Waterfall cave in the Outer Caverns.
Shortcuts	Find the secret surface route from the Outer Caverns.
Best (Robo) Friend	Reunite with Roland.
Buried Secrets	Find the fate of Caleb Vihaan within Kryptos.
CRYSTAL CRYSTAL CRYSTAL	Find the Floating Crystal in the Magma Rifts.
Echoes of the Past	Listen to your first Stub Memory.
It’s covert, honest!	Build the Covert Comms Tower.
Resistance is Futile	Uncover the truth about the Resistance.
Alpha to Omega	Reach the Omega facility.
Time is a Flat Circle	Finish the game.
Going Down	Build the Scarpa Climber’s Surface Station.

Easy to skip

Eight Jenkins figures and five base themes are the usual misses, plus the large node and cooking counts. Quakes and the Quakemaker refresh nodes. Cooking for the tablet count and crafting electronics are the grind routes in the 100% guide.

Base themes and where the guides place the unlock item.
Theme	Where
ARC	Starting theme
Yakatani	Crate after the climber in the Delta round hall
CASMACorp	Crate on a small platform at Kappa
Regis	Lambda bunker
Virtus	Lava platform outside Rho

Interior base with teal holographic panels, yellow hazard stripes, and a modular floor — Outpost interior with holo panels. Steam store screenshot for AETHUS (App 2541530). Checked 2026-10-28.

Abandoned sci-fi facility interior with crates and hazard markings — Facility interior from the official store set. Steam store screenshot for AETHUS (App 2541530). Checked 2026-10-28.

Questions

Can I miss an achievement?

Vegetarian, if you eat meat or fish. Leyren's guide calls it the only missable. The Steam description matches the diet rule.

Do hard modifiers disable achievements?

One community guide says no. Steam does not print that sentence. Change air, vitality, or carry weight freely, and treat the "no effect" line as single-source.

Sources

Steam achievements — 40 total, 19 visible, 21 hidden.
Leyren 100% guide — Missable, themes, Jenkins.

Last checked: 2026-10-28. Send corrections to [email protected].