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