Here is the full list of all 41 Pentiment achievements.
Complain to Niko about your room.
Convince Jacob Estler to save Ottilia's home.
Get Martin killed.
Get Guy killed.
Do your penance.
Get knocked out.
Win everyone's money at Lansquenet.
End Act I in the abbot's favor.
Get Ottilia executed.
Get Lucky executed.
Get Matilda executed.
Convince Gernot to let you dig up the grave.
Spin wool as fast as the ladies.
Get Wojslav to let you into the cellar.
Headbutt Werner.
Convince Illuminata to give you the French book.
Finished Act 3.
Cut enough cookies for everyone at the Christmas feast.
Learn the mystery of the cats.
Get assistance climbing down the mine shaft.
Learn about Artemis and Apollo's frog plan.
Finished Act 2.
Get Hanna killed.
Lose everything at Lansquenet.
Pass 5 dialogue checks.
Get Aedoc his medicine.
Refuse to shoot at the deer.
Shoot the deer.
Discover the imposter.
Examine 10 flowers.
Convince Endris to find his sweetheart.
Finished Act 1.
End Act I out of the abbot's favor.
Get Ferenc executed.
Tell Jacob Estler immaterial gossip.
Seduce Zdena.
Have your hat stolen.
Pet 5 animals.
Encourage Paul to draw.
Solve Ferenc's cipher with the volvelle.
Find the secret door to library.