Devil of the Plague

1. 
   First Blood

   Kill your first zombie.
   90%
2. 
   Slayer

   Kill 25 zombies.
   41%
3. 
   Executioner

   Kill 50 zombies.
   28%
4. 
   Plague Reaper

   Kill 100 zombies.
   17%
5. 
   First Key

   Collect your first key.
   87%
6. 
   Key Seeker

   Collect 5 keys.
   46%
7. 
   Key Finder

   Collect all keys in a single map.
   6.0%
8. 
   Key Master

   Collect all keys across all maps.
   0.1%
9. 
   Initiation

   Complete your first ritual.
   74%
10. 
    Ritualist

    Complete 10 rituals.
    20%
11. 
    Devoted

    Complete 50 rituals.
    1.2%
12. 
    Arch Ritualist

    Complete 100 rituals.
    0.2%
13. 
    Triple Ritual

    Complete 3 rituals in a single game.
    51%
14. 
    Master Ritual

    Complete 5 rituals in a single game.
    30%
15. 
    Perfect Ritual

    Complete a ritual without any failure.
    66%
16. 
    Final Seal

    Complete the final ritual.
    13%
17. 
    Apprentice Brewer

    Brew your first potion.
    76%
18. 
    Alchemist

    Brew 10 potions.
    6.1%
19. 
    Master Alchemist

    Brew 50 potions.
    0.1%
20. 
    Ritual Brew

    Brew 5 potions in a single game.
    2.8%
21. 
    First Shock

    Stun a boss for the first time.
    47%
22. 
    Disruptor

    Stun a boss 10 times.
    14%
23. 
    Dominator

    Stun a boss 50 times.
    0.4%
24. 
    Plague Breaker

    Stun a boss 100 times.
    0.1%
25. 
    Boss Controller

    Stun all bosses at least once.
    0.4%
26. 
    First Aid

    Revive a teammate for the first time.
    50%
27. 
    Field Medic

    Revive 25 teammates.
    1.7%
28. 
    Plague Doctor

    Revive 50 teammates.
    0.2%
29. 
    Savior

    Revive 100 teammates.
    0.1%
30. 
    Lifeline

    Save 2 teammates in a single game.
    40%
31. 
    Guardian

    Save 4 teammates in a single game.
    27%
32. 
    Chain Rescue

    Revive 3 teammates in a row.
    0.5%
33. 
    Survivor

    Win a game.
    27%
34. 
    Fallen

    Lose a game.
    83%
35. 
    Endurance

    Complete a map without dying.
    9.4%
36. 
    Immortal

    Complete all maps without dying.
    0.4%
37. 
    Last Hope

    Win as the last survivor.
    5.1%
38. 
    Unbreakable

    Win without any team deaths.
    6.4%
39. 
    Speed Runner

    Complete a game in under 20 minutes.
    6.3%
40. 
    Deathless

    Complete a game without any deaths.
    19%
41. 
    First Match

    Play your first co-op match.
    90%
42. 
    Team Player

    Play 10 co-op matches.
    1.6%
43. 
    Veteran

    Play 25 co-op matches.
    0.2%
44. 
    Elite

    Play 50 co-op matches.
    0.1%
45. 
    Unlucky

    Die 3 times.
    47%
46. 
    Doomed

    Die 10 times.
    11%
47. 
    Completionist

    Unlock all achievements.
    0.1%
48. 
    Fall of the Castle

    Complete the Castle map.
    27%
49. 
    Depths Conquered

    Complete the Dungeon map.
    8.7%
50. 
    Curse of the Sands

    Complete the Egypt map.
    5.8%

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 50 of them.