Here is the full list of all 18 Hollowed achievements.
A life after death
Choosing Oco
Meeting the god
Roaming the gods realm
Sinking deep
Seeing the future
Expressing aggression
Rejecting Life
Learning the motivation
Saving Inna
Ringing the Bells
Surviving the Collapse
Running from the past
Scaling the world
Making a trade
Avoiding the seeking hands
Moving forward decisively
Creating a relationship