Here is the full list of all 15 Amber Trail achievements.
Kill belt monster
Kill Berry hag
Kill Albast monster
Kill Poludnica monster
Kill Devil Fugas
Kill Stolem monster
Kill Cemetery hag
Kill Borowiec monster
Kill Forest hag
Kill Baba
Tell a poem to a wandering traveler
Get 100 fame points
Get 1000 fame points
Get 5000 fame points
Buy your first amber