The Way to get it to go to they's facebock and try ask the develepoer HOW to get this achievement.
Just send them this:

''Hello Play FATE I'm a big fan of your game and I just wanted to ask you one question. What the achievements "Big time hunter" and "Dungeon Master'' require? a lot people don't know, so I wanted to ask you so I can make a Guide and help some people : ) ''

That's it, that's our only hope...