Here is the full list of all 45 Blasphemous achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Unlock the ending B.
Beat His Holiness Escribar.
Beat Crisanta of the Anointed Blade.
Achieve the maximum value of health.
Beat Quirce, Returned by the Flames.
Beat all types of enemies.
Achieve the maximum value of fervor.
Bring all the offerings to the Blessed Lord of Salty Shores.
Get all relics.
Beat Melquíades, The Exhumed Archbishop.
Help the Pilgrim reach his final destination.
Buy all the items of the Candelaria shops.
Beat Exposito, Scion of Abjuration.
Bring all the offerings to Lvdovico.
Hatch the Egg of Altasgracias.
Discover all zones.
Execute 5 different enemies.
Beat Esdras, of the Anointed Legion.
Kill 666 enemies.
Witness the last moments of Viridiana.
Beat the Tres Angustias.
Beat Perpetua.
Use the Righteous Riposte 5 times.
Beat the Our Lady of the Charred Visage.
Beat Ten Piedad.
Beat the Warden of the Silent Sorrow.
Unlock the ending A.
Release all cherubs.
Talk with all the corpses.
Beat all the arena challenges.
Get all prayers.
Get all rosary beads.
Get all collectibles.
Get all sword hearts.
Achieve the maximum level of the Mea Culpa sword.
Achieve the maximum value of flasks.
Achieve the maximum value of rosary bead slots.
Visit the tomb of The Lady of the Tailed Gown.
Help Cleofás in his path of redemption.
Save all Kissers of Wounds.
Buy all skills from the Mea Culpa shrines.
Provoke the meeting between Redento and Cleofás.
Beat all bosses without flask consumption.
Cross the Bridge door in less than 3 hours.
Get 100% of the game.