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