Siegeturtle

1. 
   Polished Shell

   Enhance attributes once
   78%
2. 
   Master of the Shell

   Enhance attributes 50 times
   56%
3. 
   Strong as Shell

   Enhance attributes 120 times
   35%
4. 
   Enhancer

   Reach Lv.20 Enhance
   41%
5. 
   Blacksmith

   Reach Lv.40 Enhance
   27%
6. 
   Shellshine

   Reach Lv.80 Enhance
   10%
7. 
   Macho Turtle

   Reach 200 STR
   72%
8. 
   Shell Titan

   Reach 1000 STR
   45%
9. 
   Brainy Turtle

   Reach 200 INT
   63%
10. 
    Wise Old Shell

    Reach 2000 total stats
    63%
11. 
    New Hatchling

    Recruit 1 companion
    92%
12. 
    Growing Flock

    Recruit 15 companions
    58%
13. 
    Shell Squad

    Recruit 30 companions
    24%
14. 
    Skill Sprout

    Raise any skill to Lv.100
    59%
15. 
    Skill Grower

    Raise any skill to Lv.200
    48%
16. 
    Skill Master

    Raise any skill to Lv.500
    35%
17. 
    Skill Sage

    Raise any skill to Lv.800
    29%
18. 
    Skill Deity

    Raise any skill to Lv.1000
    27%
19. 
    Skill Legend

    Raise any skill to Lv.1500
    17%
20. 
    Equipment Collector

    Loot 10 pieces of equipment
    84%
21. 
    Treasure Diver

    Loot 1000 pieces of equipment
    48%
22. 
    Summoner’s Ripple

    Upgrade Summoning to Lv.2
    83%
23. 
    Summoner’s Tide

    Upgrade Summoning to Lv.13
    41%
24. 
    Summoner's Tsunami

    Upgrade Summoning to Lv.30
    6.4%
25. 
    Rare Shell

    Wear a Rare item
    66%
26. 
    Legendary Shell

    Equip a full set of Legendary equips
    23%
27. 
    Mystic Shell

    Wear a Mystic item
    18%
28. 
    Ancient Shell

    Equip a full set of Ancient equips
    3.5%
29. 
    Sentinel Snap

    Defeat the Sentinel at 100m
    82%
30. 
    Sentinel Crusher

    Defeat the Sentinel at 200m
    70%
31. 
    Sentinel Slayer

    Defeat the Sentinel at 600m
    49%
32. 
    Sentinel Annihilator

    Defeat the Sentinel at 1000m
    37%
33. 
    Shell vs Sentinel

    Defeat the Sentinel at 1500m
    27%
34. 
    Caller of Shells

    Defeat the Sentinel
    92%
35. 
    Summoner

    Summon 100 Sentinels
    63%
36. 
    Turtle Legion

    Summon 1000 Sentinels
    45%
37. 
    Dungeon Crawler

    Defeat Lv.30 Boss Dungeon
    63%
38. 
    Dungeon Diver

    Defeat Lv.70 Boss Dungeon
    43%
39. 
    Dungeon Dominator

    Defeat Lv.100 Boss Dungeon
    34%
40. 
    Boss Nibbler

    Defeat 100 Dungeon Bosses
    58%
41. 
    Boss Devourer

    Defeat 1000 Dungeon Bosses
    43%
42. 
    Potion Taster

    Use 1 potion
    70%
43. 
    Potion Guzzler

    Use 100 potions
    31%
44. 
    Fishing Frenzy

    Catch 1000 fish
    52%
45. 
    Star Caught

    Catch a starfish
    60%
46. 
    Pearl Collector

    Buy 10 Pearl upgrades
    54%
47. 
    Shiny Shopper

    Buy a Shiny Pearl upgrade
    56%
48. 
    Shiny Turtle

    Reach Lv.10 on a Shiny Pearl upgrade
    30%
49. 
    Back to the Reef

    Return home
    57%
50. 
    First Ascender

    Ascend 1 time
    56%
51. 
    Seasoned Ascender

    Ascend 5 times
    38%
52. 
    Ascension Master

    Ascend 10 times
    29%
53. 
    Tiny Coral

    Spend 1 Coral
    56%
54. 
    Coral Spender

    Spend 50 Coral
    35%
55. 
    Coral Overflow

    Spend 200 Coral
    24%
56. 
    Hidden PowerSecret

    Steam withholds the description of a secret achievement.
    22%
57. 
    Milestone Stepper

    Claim 10 milestones
    75%
58. 
    Milestone Marathon

    Claim 100 milestones
    36%
59. 
    Milestone Titan

    Claim 150 milestones
    16%
60. 
    Challenge Accepted

    Complete a Challenge
    41%
61. 
    Challenge Conqueror

    Complete a Tier II Challenge
    25%
62. 
    Medal Collector

    Obtain 5 Challenger Medals
    32%
63. 
    Ultimate Turtle

    Obtain all Challenger Medals
    17%
64. 
    Level Up!

    Reach turtle level 50
    57%
65. 
    Level Master!

    Reach turtle level 200
    32%
66. 
    Level Legend!

    Reach turtle level 600
    19%
67. 
    Level God!

    Reach turtle level 1000
    3.8%
68. 
    Strong

    Spend 100 GP in a single ascension
    48%
69. 
    Very Strong

    Spend 500 GP in a single ascension
    31%
70. 
    Stronger

    Spend 1000 GP in a single ascension
    27%
71. 
    Strongest

    Spend 2000 GP in a single ascension
    24%
72. 
    The Journey Begins

    Travel a cumulative total of 1000m distance
    79%
73. 
    Ocean Traveller

    Travel a cumulative total of 10000m distance
    56%
74. 
    Endless Voyage

    Travel a cumulative total of 10000000m distance
    18%

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 74 of them.