I see the problem this way:
People are hunting creatures -very dangerous creatures- with impunity for profit and sport.
Very dangerous creatures are not hunting people.
Solution:
Get rid of spawns -static or random- and put an actual mind behind the actions, movements, buildup, and purpose of the very angry creatures the ignorant 'gods' displaced while making room for their whiny wish for worshippers. Create a realistic system of creation and resource for the origins of each creature, then an easy way to direct them singly or en mass. An NPC AI will never be able to duplicate the deviousness of a real person.
Face it, until the creatures have a purpose, they are pointless. And I include training and gaining loot in with 'pointless'. Put training where it belongs.