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