Here is the full list of all 39 Blacksad: Under the Skin achievements.
Do not scare Brunhilda while telling her a story.
Complete the game dying less than 9 times.
Now for real.
Complete all deductions in the game.
Solve the case.
Beat someone up for once.
Take your sixth beating.
Play baseball.
Play good cop convincingly.
Take your fifth beating.
Put your acting skills to the test.
Charm Helen Moore into giving you a present.
Take your fourth beating.
Get hired twice for the same case.
Buy a box of cigarettes from the nursing staff.
Take a ride with the city's most honest bookmarker.
Take your third beating.
Buy your favorite goat a second burger.
Take 400 nightstick blows. Maybe a few less.
Take your second beating.
Find your most valuable tool.
Take your first beating (spoiler: it won't be the last!).
Complete the game without dying a single time.
Complete the Hockey sheet of the Hall of Fame album.
Complete the Football sheet of the Hall of Fame album.
Complete the Boxing sheet of the Hall of Fame album.
Complete the Baseball sheet of the Hall of Fame album.
Complete the Hall of Fame album.
Why's that poster in Dunn's flat?
Interact with as many books as you can.
Do not take the case.
Find all false endings in the game.
Watch all 6 alternate scenes at the end of the game.
Contribute to as many deaths as possible.
Complete Blacksad's silence conveniently.
Stand up to Sam as many times as you can.
Stand up to Quince as many times as you can.
Play bad cop convincingly.
Help the Colberts live a second honeymoon and receive their gratitude.