53 known values for icon with current usage counts:

1. default (30073× used)
2. angel_wings (8387× used)
3. crown (6343× used)
4. joystick (6266× used)
5. moon (4061× used)
6. sakura (2211× used)
7. cat (1924× used)
8. dog (1663× used)
9. spider (1218× used)
10. pumpkin (722× used)
11. vampire (625× used)
12. headphones (549× used)
13. target (516× used)
14. sunglasses (511× used)
15. moustache (364× used)
16. coffee (305× used)
17. skill_issue (288× used)
18. panda (213× used)
19. snowflake (159× used)
20. santa (110× used)
21. pirate_flag (77× used)
22. wizard (77× used)
23. reindeer (75× used)
24. king (66× used)
25. octopus (62× used)
26. yeti (54× used)
27. rocket (47× used)
28. bad_bunny (47× used)
29. lunar_dragon (44× used)
30. wanted (43× used)
31. koala (37× used)
32. mountains (34× used)
33. bingo (31× used)
34. ghost (30× used)
35. planet (29× used)
36. bread (28× used)
37. pyramid_eye (28× used)
38. pirate (24× used)
39. robot (20× used)
40. cactus (19× used)
41. watermelon (16× used)
42. shark_attack (16× used)
43. cute_bunny (16× used)
44. fossil (14× used)
45. eliminated (11× used)
46. jailbreak (9× used)
47. clover (8× used)
48. pine_tree (5× used)
49. ankh (5× used)
50. bauble (3× used)
51. shooting_star (2× used)
52. palette (2× used)
53. eleven (1× used)