Here is the full list of all 27 Forgotten Fables: Wolves on the Westwind achievements.
Outrun the outlaws and make it to Isleifsfell
Defeat the Peaceless outlaws in Hjallvik
Learn your first new skill or spell
Witness the return of the Fiend of Lolgramoth
Complete Act 1 of Wolves on the Westwind
Steal the journal from inside Hjalsingor's vault
Take the Demon's Tooth from the Alkenfelsen
Take a pact with the agent of the Nameless One
Fall to your death in the caves of the Alkenfelsen
Ignore the pact to try to help a friend
Complete Act 2 of Wolves on the Westwind
Learn why you are being hunted by the Fiend of Lolgramoth
Complete the raid on the Nostrian outpost
Exile Orlvir from the Wolves on the Westwind
Make Orlvir face the Fiend of Lolgramoth
Make it to the confrontation against the Fiend of Lolgramoth with every companion
Kill the Fiend of Lolgramoth
Join the Wolves on the Westwind
Complete Act 3 of Wolves on the Westwind
Complete the game with Alrik
Complete the game with Nedime
Complete all chapters of Estrid's story line
Complete all chapters of Raskir's story line
Complete all chapters of Swafnild's story line
Complete all chapters of the elf's story line
Complete all chapters of Maednir's story line
Receive an invitation to the feast with Hetman Firunjasson and his family