Here is the full list of all 20 Beyond the Wall achievements.
Killed by Skeleton
Destroy all obstacles
Killed by Wolf
Frozen to death
Survive for 100 days
Survive for 90 days
Survive for 80 days
Survive for 70 days
Get 100 health
Survive for 60 days
Survive for 50 days
Survive for 40 days
Survive for 30 days
Collect all food except meat
Survive for 20 days
Get 300 health
Survive for 10 days
Get 200 health
Collect all food on the level
Collect mushroom