Here is the full list of all 16 Dark Grim Mariupolis achievements.
Finished the game
Finished the game without killing Sergio.
You can take your time.
Opened the Naropolus' door
Defeated the Laser Cat
Defeated the Viking Guard
Died the first time
Repaired and scavenged the robots.
Solved the cross-smile puzzle in an unusual way
This book is pretty interesting, isn't it?
Finished the prologue.
Solved the RGB puzzle.
Challenged Pentatonic's priest for a duel
Died the second time
Win all the duels
There will be no more death-in-a-duel achievements.