Portal: Revolution

1. 
   Pacifist

   Complete the Chamber 4-9 without knocking over any turrets
   5.7%
2. 
   Sending a message

   Blow up a test chamber sign
   21%
3. 
   Refreshing shower

   Take a shower under one of the gel cleansing fields
   5.7%
4. 
   Just in time

   Deplete the conveyors' supply of Weighted Storage Cubes
   6.1%
5. 
   Captivating Looks

   Stare at Conly's mannequins for a really long time
   7.8%
6. 
   Fingerprinter

   Smear your dirty fingers over Aperture's beautiful glass
   4.9%
7. 
   To the surface and beyondSecret

   Steam withholds the description of a secret achievement.
   50%
8. 
   Journey CompleteSecret

   Steam withholds the description of a secret achievement.
   41%
9. 
   New friendsSecret

   Steam withholds the description of a secret achievement.
   38%
10. 
    Upgrade?Secret

    Steam withholds the description of a secret achievement.
    45%
11. 
    Let's do this one last timeSecret

    Steam withholds the description of a secret achievement.
    35%
12. 
    Back to bedSecret

    Steam withholds the description of a secret achievement.
    31%
13. 
    Endless loop

    Fling in an endless loop in Chamber 4-11
    14%
14. 
    Supply Chain Problems

    Deplete the gel supply in Chamber 4-11
    5.7%
15. 
    Two times the charm

    Solve the Chamber 6-2 twice
    5.6%
16. 
    Still a pacifist

    Complete Chamber 5-1 without destroying any turrets
    5.5%
17. 
    The boring solution

    Solve Chamber 6-6 the boring way
    27%
18. 
    The fun solution

    Solve Chamber 6-6 the fun way
    18%
19. 
    HiredSecret

    Steam withholds the description of a secret achievement.
    63%
20. 
    Bullseye

    Get the ball in 4-10 to land perfectly in the socket
    21%
21. 
    VolunteerSecret

    Steam withholds the description of a secret achievement.
    91%

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 21 of them.