Here is the full list of all 32 Röki achievements.
Complete the game
Open the gate to the tower
Solve the sundial puzzle
Solve the dining hall puzzle
Complete Chapter 2
See beyond the veil
Awaken Jötunbjørn
Open all of the Rootways
Create a new path in the church
Awaken Jötunúlfur
Have Fossegrim charm an instrument
Escape from the waterlogged caves
Activate the ice altar
Summon a Tomte
Rescue the Great Mother Tree
Help a troll
Explore off the beaten track
Complete Chapter 1
Escort Lars to the outhouse
Successfully combine two items
Examine 50 unique backpack items
Read every gravestone
Get to know the mill Tomte
Find all of the petrified Trollbrothers
Return Trollhilde's gold
Spin the top 5 times
Insult Shroomi
Find all of the castle explorer's notes
Say everything that needs to be said
Get to know the castle's inhabitants
Find all the Guardian banners in the castle
Acquire all other badges