137

1. 
   All-Seeing Eye

   Read a data chip for the first time
   23%
2. 
   A Tumour

   Discover a room of flesh
   7.6%
3. 
   Code Whisperer

   Enter a secret command
   15%
4. 
   Aerial Spirit

   Fend off the creature lurking on the Skydeck
   7.6%
5. 
   Unalloyed

   Complete a run without a single Concept
   15%
6. 
   Records of 136

   Encounter a vengeful iteration
   31%
7. 
   Cerebral Expansion

   Read 10 unique data chips
   7.6%
8. 
   Of One Mind

   Obtain an Exo Module for the first time
   31%
9. 
   Xanthous Element

   Noclip out of reality
   0.0%
10. 
    Ephemeral Lance

    Discover the Red Spire
    7.6%
11. 
    Cursecatcher

    Obtain a cursed Concept for the first time
    31%
12. 
    The IteratorSecret

    Steam withholds the description of a secret achievement.
    46%
13. 
    The Living FactorySecret

    Steam withholds the description of a secret achievement.
    0.0%
14. 
    The ProjectionSecret

    Steam withholds the description of a secret achievement.
    0.0%
15. 
    The UsurperSecret

    Steam withholds the description of a secret achievement.
    0.0%
16. 
    Torn Portrait

    Visit the dark Underbelly of the facility
    15%
17. 
    Sidequest!

    Score at least 1,000 in Little Fox's Adventure
    0.0%
18. 
    Monster Hunter

    Unlock every tier 3 entry in the Threat Log
    0.0%
19. 
    Bookworm

    Read every data chip in the facility
    0.0%
20. 
    Dispatch Agent

    Win a run with 100% task completion rate
    7.6%
21. 
    Elemental Confluence

    Experience every unique weather type in one run
    0.0%
22. 
    High Score

    Score at least 10,000 in a run
    23%
23. 
    Bloodfest

    Eliminate over 100 threats in a single run
    23%
24. 
    Limit Breaker

    Increase any stat to at least double its base value
    46%
25. 
    Iterator

    Beat a run on Iterator difficulty
    0.0%
26. 
    Flesh Vessel

    Beat a run on Flesh Vessel difficulty
    0.0%
27. 
    Collapsing

    Beat a run on Collapsing difficulty
    0.0%
28. 
    Lunar Ammonite

    Discover a creature fallen from the stars
    7.6%
29. 
    Organics Module

    Iterate 10 times
    31%
30. 
    Total Experimental Success

    Achieve any ending with every Variable active
    0.0%
31. 
    Deepsea Predator

    Find a friend lurking in the waters
    7.6%
32. 
    Unraveling...

    Witnessed the dawn of the facility's 1000th sun
    0.0%
33. 
    Eager Witness

    Unlock all facility expansions
    0.0%
34. 
    Liquid Smooth

    Complete a run without any fluid going critical
    7.6%
35. 
    Ice Spikes

    Freeze a Concept for another time in the Cold Storage
    0.0%
36. 
    Celestium

    Reach the highest point in the facility
    15%
37. 
    Extraplanar Visitor

    Encounter an extraterrestrial
    0.0%
38. 
    Abyss Herald

    Find a way to cheat death
    0.0%
39. 
    Buried Sector

    Reach 50% achievement completion
    0.0%
40. 
    Freight Hoist

    Hold at least 20 Concepts at one time
    38%
41. 
    Bile Nexus

    Witness the Organic Module's transformation
    0.0%
42. 
    Memory Corruption

    Encounter a digital anomaly
    7.6%
43. 
    Precipitate Rail

    Descend to the Buried Sector in round 9 or earlier
    0.0%

Names, descriptions and icons are the game’s own, as Steam publishes them; the share is how many owners have unlocked each, from Steam's global figures for 43 of them.