54 known values for icon with current usage counts:

1. default (31314× used)
2. angel_wings (8642× used)
3. crown (6502× used)
4. joystick (6397× used)
5. moon (4170× used)
6. sakura (2324× used)
7. cat (1997× used)
8. dog (1715× used)
9. spider (1217× used)
10. pumpkin (724× used)
11. vampire (626× used)
12. headphones (554× used)
13. target (519× used)
14. sunglasses (513× used)
15. moustache (369× used)
16. skill_issue (304× used)
17. coffee (304× used)
18. panda (210× used)
19. snowflake (159× used)
20. santa (109× used)
21. pirate_flag (78× used)
22. king (75× used)
23. reindeer (74× used)
24. wizard (74× used)
25. octopus (62× used)
26. yeti (56× used)
27. lunar_dragon (52× used)
28. bad_bunny (49× used)
29. wanted (47× used)
30. rocket (47× used)
31. koala (41× used)
32. mountains (39× used)
33. bingo (33× used)
34. planet (32× used)
35. bread (32× used)
36. pyramid_eye (31× used)
37. ghost (30× used)
38. pirate (24× used)
39. robot (24× used)
40. cactus (24× used)
41. shark_attack (17× used)
42. eliminated (16× used)
43. cute_bunny (16× used)
44. fossil (16× used)
45. watermelon (15× used)
46. jailbreak (10× used)
47. clover (10× used)
48. ankh (6× used)
49. pine_tree (5× used)
50. bauble (3× used)
51. shooting_star (2× used)
52. build_off (1× used)
53. eleven (1× used)
54. palette (1× used)