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.
Aid a questing knight.
Achieve the maximum devotion level in your creed.
Aid an unraveling sorceror.
Achieve the maximum upgrade level of a weapon.
Take an oath to the gods of Fire and Sky.
Take an oath to the Order of the Betrayer.
Bear all possible brands.
Aid a despondent thief.
Take an oath to The Three.
Take an oath to Devara's Light.
Take an oath to The House of Splendor.
Discover your first brand.
Defeat the Kraekan Cyclops.
Defeat the Mad Alchemist.
Take an oath to The Stone Roots.
Defeat the Queen of Smiles.
Defeat the Sodden Knight.
Claim your first sanctuary.
Take an oath to The Iron Ones.
Defeat the Unspeakable Deep.