Full list of all 43 The Council achievements worth 1,000 gamerscore. It takes around 4-5 hours to unlock all of the achievements in the base game on Xbox One.
The base game contains 30 achievements worth 590 Gamerscore, and there are 5 DLC packs containing 13 achievements worth 410 Gamerscore.
Choose to follow sir Gregory and Cardinal Piaggi
Become an occultist
Raise a skill to level 3
Join Emily Hillsborrow in your room
Use exactly one consumable of each type during a quest
Convince Emily Hillsborrow of the purity of your intentions when she surprises you in her room
Conduct the investigation about your vision
Become a diplomat
Complete episode 1
Reach level 5
Accept to follow Elizabeth Adams
Draw Emily Hillsborrow's secret out of her
Overcome 5 confrontations
Open Pandora's box
Acquire ten skills of level 1 in the same game
Complete the third quest
Persuade Napoleon that he can trust you
Manage to get Elizabeth Adams to talk about her past
In the same game, choose 20 answers before the time is up
Drop to 0 effort points during a quest
Complete the second quest
Avoid being used as a punchbag by Jacques Péru
Assist George Washington
Complete a quest without using consumables
Complete the first quest
Choose to stay with George Washington and Emily Hillsborrow
Persuade Cardinal Piaggi to give you the letter
Become a detective
Be disfigured by Gerard von Borchert
Get rid of Von Borchet with your mother
Complete episode 2
Complete the sixth quest
Complete the fifth quest
Complete episode 3
Complete the ninth quest
Complete the eighth quest
Complete episode 4
Complete the twelfth quest
Complete the eleventh quest
Complete the story
Complete the fifteenth quest
Complete the fourteenth quest
Reach level 15