I've only seen one story that uses puzzles instead of brute force to get rid of intruders that are meat heads, I forget the name aswell, if anyone has read a story like this or wish to use this idea please post your chapter in the comments.

  ps if anyone knows the name of the girl who ran a dungeon, became a god of chaos, drove a hero away by a simple puzzle and almost drove the demon lords daughter crazy with the multiple harder puzzles she set up after that hero left in shame, please remind me of it's name.