Bestiary entry from the Clan Primer:
This creature always drops a trophy when it is defeated. This trophy is used in the Hunt Club side quest which involves trading in the trophies for items, armor and accessories.
|Common - (55%)||Close Helmet|
|Uncommon - (10%)||(Nothing)|
|Rare - (3%)||(Nothing)|
* The Zombie Lord will appear somewhere in the Northfall Passage of the Tomb of King Raithwall when the game’s minute timer is between 0 minutes and 29 minutes. Additionally, you need to have initiated the Hunt Club side quest in order for it to appear.