68 known values for trail with current usage counts:

1. default (25571× used)
2. fluff (9165× used)
3. yellow_dots (5156× used)
4. red (2206× used)
5. paws (1413× used)
6. fire (1310× used)
7. rings (1300× used)
8. blue (1233× used)
9. green (1093× used)
10. earth (1065× used)
11. ice (939× used)
12. arcade (929× used)
13. red_neon (841× used)
14. stardust (703× used)
15. blue_neon (567× used)
16. fire_dust (540× used)
17. ice_dust (531× used)
18. sakura (510× used)
19. flowers (477× used)
20. shadow_dust (438× used)
21. autumn_leaves (396× used)
22. magic (380× used)
23. crimson (353× used)
24. digital_3d (287× used)
25. fire_tail (268× used)
26. shadow_tail (253× used)
27. abstract_3d (189× used)
28. magic_dust (189× used)
29. elements (183× used)
30. magic_tail (181× used)
31. ice_tail (173× used)
32. wish (156× used)
33. stars (61× used)
34. speedy (61× used)
35. black_and_white (60× used)
36. tech_path (58× used)
37. tracks (46× used)
38. green_neon (44× used)
39. pollution (42× used)
40. feathers (37× used)
41. leaves (37× used)
42. snowflakes (29× used)
43. pumpkins (28× used)
44. twinkles (28× used)
45. siren (28× used)
46. aaaaa (27× used)
47. red_dots (25× used)
48. treasure_map (25× used)
49. zzzzz (21× used)
50. dots_inc (21× used)
51. festive_tree (20× used)
52. propulsion (20× used)
53. lunar_fireworks (19× used)
54. bubbles (14× used)
55. rainbow_light (9× used)
56. blue_plasma (9× used)
57. ghost (8× used)
58. money_trail (7× used)
59. lucky_trail (6× used)
60. rainbow_dots (5× used)
61. confetti (5× used)
62. bomb_fuse (5× used)
63. spacewar (4× used)
64. gold (2× used)
65. red_plasma (2× used)
66. gold_dust (2× used)
67. meteorite (1× used)
68. musical_notes (1× used)