68 known values for trail with current usage counts:

1. default (28364× used)
2. fluff (10426× used)
3. yellow_dots (6281× used)
4. red (2908× used)
5. blue (1952× used)
6. paws (1589× used)
7. green (1526× used)
8. fire (1296× used)
9. rings (1295× used)
10. earth (1076× used)
11. ice (944× used)
12. arcade (924× used)
13. red_neon (842× used)
14. stardust (722× used)
15. flowers (652× used)
16. ice_dust (619× used)
17. blue_neon (575× used)
18. fire_dust (550× used)
19. sakura (529× used)
20. shadow_dust (520× used)
21. magic (406× used)
22. crimson (394× used)
23. shadow_tail (382× used)
24. autumn_leaves (379× used)
25. digital_3d (357× used)
26. fire_tail (328× used)
27. abstract_3d (322× used)
28. elements (303× used)
29. ice_tail (288× used)
30. magic_tail (267× used)
31. magic_dust (208× used)
32. wish (193× used)
33. black_and_white (140× used)
34. stars (74× used)
35. speedy (72× used)
36. tech_path (59× used)
37. pollution (53× used)
38. red_dots (52× used)
39. tracks (44× used)
40. leaves (43× used)
41. green_neon (43× used)
42. feathers (41× used)
43. siren (40× used)
44. snowflakes (38× used)
45. treasure_map (37× used)
46. propulsion (35× used)
47. zzzzz (30× used)
48. aaaaa (30× used)
49. pumpkins (29× used)
50. festive_tree (29× used)
51. lunar_fireworks (23× used)
52. dots_inc (21× used)
53. twinkles (21× used)
54. bubbles (16× used)
55. rainbow_light (12× used)
56. bomb_fuse (12× used)
57. ghost (11× used)
58. blue_plasma (11× used)
59. lucky_trail (11× used)
60. money_trail (10× used)
61. rainbow_dots (9× used)
62. red_plasma (8× used)
63. confetti (7× used)
64. spacewar (5× used)
65. meteorite (3× used)
66. gold_dust (3× used)
67. gold (2× used)
68. musical_notes (1× used)