Here is the full list of all 17 Leviathan: The Last Day of the Decade achievements.
You speak, see and do no evil. No evil at all.
Fin
The maniac is jailed. Why do you feel so depressed and upset?
Some new clues and a new enemy! It seems you investigation goes well.
You took away the gargoyle's heart.
Kristian told you about his dog.
You've found more than you ever wished for at the Kroistham Archive.
Now you know how that story began.
It seems, Ruth thinks that you are special, so you deserve something more than friendship.
You've got an old Oliver Vertran's photo.
You tasted all the potions made by the vending machine.
The guard told you a story by Phill from Chancellery. What a thrilling shit!
Sometimes your sister reminds you about the things you'd like to forget.
You've found some evil books made from human skin at the Kroistham severs!
You know Kroistham subway well.
You are the man of disgusting deeds.
Fistful and pockets of gold! Yeah, you are the real Orvood heir.