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