68 known values for trail with current usage counts:

1. default (28045× used)
2. fluff (9841× used)
3. yellow_dots (6023× used)
4. red (2817× used)
5. blue (1884× used)
6. paws (1515× used)
7. green (1488× used)
8. rings (1305× used)
9. fire (1303× used)
10. earth (1074× used)
11. ice (940× used)
12. arcade (922× used)
13. red_neon (839× used)
14. stardust (717× used)
15. flowers (615× used)
16. ice_dust (592× used)
17. blue_neon (574× used)
18. fire_dust (549× used)
19. sakura (525× used)
20. shadow_dust (486× used)
21. magic (396× used)
22. crimson (390× used)
23. autumn_leaves (385× used)
24. shadow_tail (352× used)
25. digital_3d (336× used)
26. fire_tail (316× used)
27. abstract_3d (296× used)
28. elements (289× used)
29. ice_tail (270× used)
30. magic_tail (252× used)
31. magic_dust (202× used)
32. wish (183× used)
33. black_and_white (89× used)
34. stars (73× used)
35. speedy (69× used)
36. tech_path (58× used)
37. pollution (51× used)
38. tracks (47× used)
39. leaves (43× used)
40. green_neon (43× used)
41. feathers (38× used)
42. red_dots (37× used)
43. siren (36× used)
44. treasure_map (33× used)
45. snowflakes (33× used)
46. zzzzz (31× used)
47. propulsion (31× used)
48. aaaaa (29× used)
49. festive_tree (28× used)
50. pumpkins (28× used)
51. twinkles (24× used)
52. dots_inc (22× used)
53. lunar_fireworks (21× used)
54. bubbles (15× used)
55. bomb_fuse (11× used)
56. lucky_trail (11× used)
57. rainbow_light (10× used)
58. blue_plasma (10× used)
59. money_trail (9× used)
60. rainbow_dots (9× used)
61. ghost (8× used)
62. confetti (8× used)
63. red_plasma (6× used)
64. spacewar (5× used)
65. meteorite (3× used)
66. musical_notes (2× used)
67. gold (2× used)
68. gold_dust (2× used)