Stereotypically, they are the kind of simple riddles as described below, but modern treatments generally prefer to have the character use more sophisticated puzzles.

That was a simple riddle used by Zen Masters in the training of monks, Joe remembered.

After much wandering, Homer finally died on the Aegean island of Ios, friendless and alone, unable to answer a simple riddle put to him by young fisher-boys.

The first is to look upon it as a simple riddle to which the Scribes seemingly had no answer.

On the card was written a simple riddle.

The smile on his evil lips was an answer to the simple riddle that The Shadow had already solved.

They played guessing games, but its lack of local cultural knowledge handicapped it, just as Flach'f, lack of knowledge about Hectare conventions made some supposedly simple riddles impervious to his comprehension.

The challenges are clustered in four levels of difficulty, which range from simple riddles solvable with paper-and-pencil to mathematical challenges from modern cryptanalysis for researchers and experts.

He started out with some simple riddles.

It was as if a projectionist kept stopping the movie to ask you simple riddles, then showed you a little more once you had answered.