Here is the full list of all 22 Witch Hunt achievements.
Find the book of the dead.
Find the weird looking skull.
Finish game not using any silver crucifixes or watcher totems.
Finish the game without dying.
Don't get hurt by a whisperer.
Finish game in perma mode.
Unlock 5 chests in one playthrough.
Unlock and visit every location behind locked doors.
Finish the game.
Unlock all skills in one playthrough.
Kill the witch.
Find all save stones in the game.
Destroy the sacrificial tree.
Kill 3 deadblind in one playthrough.
Kill the beast.
Make 20 headshots in one playthrough.
Kill 50 enemies in one playthrough.
Fire a cannon.
Attack enemy with lightning using thunder totem.
Kill the night flier.
Save a dog.
Attack the beast.