Here is the full list of all 18 Bone Marrow achievements.
Open the mace "128"
Open battle ax "256"
Open ax "512"
Open porridge "128"
Open the pie "256"
Open the potion "512"
Open cavalry shield "128"
Open the fencing shield "256"
Open the knight’s shield "512"
Destroy the rat
Destroy the snake
Destroy the skeleton king
Destroy the king of the dead
Destroy the Ghoul King
Open druid
Score 3000 points
Score 5000 points
Score 9000 points