For Vivid Imaginations

Developed in 1974, Dungeons & Dragons used medieval characters and mythical creatures to resonate with a core of devotees. The game known for its oddly shaped dice became a hit, particularly among teenage boys with vivid imaginations, and eventually was turned into video games, books and movies.

Dungeons & Dragons players create fictional characters and carry out their adventures following complicated rules. The cult pastime spawned a wealth of copycat games and later inspired a genre of computer games that is still growing in popularity.

Gary Gygax, who co-created the fantasy game and helped start the role-playing phenomenon, died Tuesday at his home in Lake Geneva, Wis. He was 69.