Mortal Shell

1. 
   Forever Alone

   Beat the game without ever bonding with a shell
   1.9%
2. 
   Face Off

   Defeat Hadern in the tutorial
   6.9%
3. 
   Seeker of False Truths

   Unlock all secret lore
   2.1%
4. 
   Fun Guy

   Pick 50 mushrooms
   25%
5. 
   Step Goal

   Kill an enemy with bear trap
   26%
6. 
   Life is SufferingSecret

   Steam withholds the description of a secret achievement.
   1.9%
7. 
   Brigand Life

   Waste your life away with Baghead
   11%
8. 
   Bars Tended

   Become familiar with all items
   2.3%
9. 
   Flesh And Instinct

   Find your first Shell
   85%
10. 
    Is This a Sparta?

    Kill an enemy by kicking them off a platform
    8.3%
11. 
    Bring the Glands Back to MeSecret

    Steam withholds the description of a secret achievement.
    19%
12. 
    The Good Time are Killing MeSecret

    Steam withholds the description of a secret achievement.
    11%
13. 
    Sugar Baby

    Spend over 50, 000 Tar in Vlad's Shop
    3.7%
14. 
    Untarnished

    Parry over 100 attacks
    7.1%
15. 
    You Seem Different...

    Unlock all of the shells in the game
    24%
16. 
    Different Kinds of GrishaSecret

    Steam withholds the description of a secret achievement.
    13%
17. 
    Crossed the ThresholdSecret

    Steam withholds the description of a secret achievement.
    13%
18. 
    Faded the FireSecret

    Steam withholds the description of a secret achievement.
    19%
19. 
    Martyr'd the MatyrSecret

    Steam withholds the description of a secret achievement.
    17%
20. 
    Tragic LossSecret

    Steam withholds the description of a secret achievement.
    15%
21. 
    Felled the GlandfatherSecret

    Steam withholds the description of a secret achievement.
    13%
22. 
    Nailed ItSecret

    Steam withholds the description of a secret achievement.
    4.4%
23. 
    It's a meSecret

    Steam withholds the description of a secret achievement.
    4.8%
24. 
    The NihilistSecret

    Steam withholds the description of a secret achievement.
    4.2%
25. 
    PurrfectSecret

    Steam withholds the description of a secret achievement.
    36%
26. 
    Gateway Drug

    Spend 100,000 tar in The Virtuous Cycle
    2.6%
27. 
    SeedbearerSecret

    Steam withholds the description of a secret achievement.
    2.2%
28. 
    True NektarSecret

    Steam withholds the description of a secret achievement.
    1.7%
29. 
    Fashion Shells

    Unlock all Shell Shades for The Virtuous Cycle
    1.6%
30. 
    Lute Hero

    Max familiarity with all of the game's lutes
    3.8%
31. 
    OP AF

    Acquire 100 instincts in one cycle
    2.3%
32. 
    Change of Heart

    Return a seed with Hadern in The Virtuous Cycle
    1.7%
33. 
    Master of None

    Acquire all 4 weapon Instincts for the Axatana in one cycle
    2.2%
34. 
    No Lifer

    Complete a run in The Virtuous Cycle with the Dark Form Obsidian Shell Shade
    1.6%
35. 
    There Can Only Be One

    Beat all variations of the Dark Shells in The Virtuous Cycle
    1.6%
36. 
    The Answer

    Fully Upgrade Hadern's skill tree
    3.5%
37. 
    Some Assembly Required

    Transform the Axatana between different modes
    9.9%

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 37 of them.