Here is the full list of all 37 Salt and Sanctuary achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
Defeat the Unspeakable Deep.
Aid a questing knight.
Take an oath to the Order of the Betrayer.
Take an oath to the gods of Fire and Sky.
Take an oath to The Iron Ones.
Take an oath to The House of Splendor.
Take an oath to Devara's Light.
Take an oath to The Stone Roots.
Aid an unraveling sorceror.
Achieve the maximum upgrade level of a weapon.
Achieve the maximum devotion level in your creed.
Bear all possible brands.
Aid a despondent thief.
Discover your first brand.
Defeat the Kraekan Cyclops.
Defeat the Mad Alchemist.
Defeat the Queen of Smiles.
Defeat the Sodden Knight.
Claim your first sanctuary.
Take an oath to The Three.