Here is the full list of all 50 Black Book achievements.
Guess the road in the cursed forest
Don't release the Mermaid
Become a mistress of Hell
Collect 4 copies of each card
Unlock all the words
Succumb to Dark forces
Meet your beloved one
Complete Chapter 7
Compose a spell out of 13 words
Unlock all the black words
Win 3 times in a card game while cheating
Break all the seals
Complete Chapter 6
Retrieve the Book
Collect all the songs
Collect 70 encyclopedia entries
Complete Chapter 5
Collect 50 bailichkas
Visit 333 locations
Acquire 100 sins
Complete Karnysh loyalty quest
Talk with 100 characters
Complete Chapter 4
Find all the clues in Nemzya
Gather 66 herbs
Complete Chapter 3
Answer 40 Knowledge questions
Collect 30 bailichkas
Read 77 entries in the Onomasticon
Complete Old Egor loyalty quest
Take seven demons to your service
Complete Chapter 2
Release the Mermaid
Complete Proshka loyalty quest
Gather 33 herbs
Complete White Head loyalty quest
Answer 25 Knowledge questions
Cow level
Release seven dead men
Collect 30 encyclopedia entries
Negotiate with Susedko on Zemskaia station
Gather 13 herbs
Complete Chapter 1
Guess all the Obderiha riddles with the first attempt
Collect 10 bailichkas
Complete Nikolay loyalty quest
Answer 10 Knowledge questions
Win 5 times in a card game
Collect 10 encyclopedia entries
Complete the Prologue