Here is the full list of all 26 Shadow Gambit: The Cursed Crew achievements.
Get 70% overall completion.
Finish Gaëlle's Crew Tale.
Get 60% overall completion.
Finish Act 3.
Get 50% overall completion.
Finish Teresa's Crew Tale.
Get 40% overall completion.
Unlock all characters.
Get 30% overall completion.
Finish Pinkus' Crew Tale.
Discover all islands.
Finish your first Captain's Test.
Finish Toya's Crew Tale.
Finish Act 2.
Get 20% overall completion.
Collect all of Mordechai's Relics.
Unlock your first skill upgrade.
Finish Suleidy's Crew Tale.
Get 10% overall completion.
Finish Act 1.
Set sail with the Marley for the first time.
Get 80% overall completion.
Unlock all skill upgrades.
Finish Quentin's Crew Tale.
Finish John's Crew Tale.
Unlock Virgilio.