68 known values for trail with current usage counts:

1. default (27493× used)
2. fluff (9540× used)
3. yellow_dots (5779× used)
4. red (2660× used)
5. blue (1700× used)
6. paws (1459× used)
7. green (1362× used)
8. fire (1311× used)
9. rings (1304× used)
10. earth (1065× used)
11. ice (945× used)
12. arcade (934× used)
13. red_neon (834× used)
14. stardust (710× used)
15. blue_neon (567× used)
16. ice_dust (566× used)
17. fire_dust (545× used)
18. flowers (524× used)
19. sakura (520× used)
20. shadow_dust (468× used)
21. magic (392× used)
22. autumn_leaves (387× used)
23. crimson (382× used)
24. shadow_tail (315× used)
25. digital_3d (312× used)
26. fire_tail (294× used)
27. abstract_3d (238× used)
28. elements (235× used)
29. ice_tail (231× used)
30. magic_tail (219× used)
31. magic_dust (198× used)
32. wish (174× used)
33. black_and_white (73× used)
34. speedy (70× used)
35. stars (66× used)
36. tech_path (60× used)
37. pollution (49× used)
38. tracks (45× used)
39. leaves (42× used)
40. green_neon (42× used)
41. feathers (37× used)
42. siren (34× used)
43. snowflakes (30× used)
44. treasure_map (29× used)
45. festive_tree (29× used)
46. propulsion (28× used)
47. aaaaa (28× used)
48. pumpkins (28× used)
49. zzzzz (27× used)
50. red_dots (26× used)
51. twinkles (25× used)
52. dots_inc (21× used)
53. lunar_fireworks (20× used)
54. bubbles (14× used)
55. rainbow_light (10× used)
56. money_trail (9× used)
57. ghost (9× used)
58. blue_plasma (9× used)
59. bomb_fuse (8× used)
60. confetti (8× used)
61. rainbow_dots (8× used)
62. lucky_trail (7× used)
63. red_plasma (5× used)
64. spacewar (4× used)
65. gold_dust (2× used)
66. gold (2× used)
67. musical_notes (1× used)
68. meteorite (1× used)