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