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

He had been suffering from health problems for several years, including an abdominal aneurysm, said his wife, Gail Gygax.

Gygax and Dave Arneson developed Dungeons & Dragons in 1974 using medieval characters and mythical creatures. 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.

Gygax expected that the game would resonate with a core of devotees.

"It only surprised me up until around 1977," he told Canada's National Post in a 2005 interview. "I had thought we were going to have a considerable audience of gamers and science fiction and fantasy fans. . . . But when people began to write me [with questions] about what fantasy books to read, and I saw the wide range of both younger and older people who were attracted to the game, I understood that it was reaching a deeper chord, something deep within us."

Gygax always enjoyed hearing from the game's legion of devoted fans, many of whom would stop by the family's home in Lake Geneva, near Milwaukee, his wife said. Despite his declining health, he hosted weekly games of Dungeons & Dragons as recently as January, she said.

"It really meant a lot to him to hear from people from over the years about how he helped them become a doctor, a lawyer, a policeman -- what he gave them," Gail Gygax said.

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.

The game was criticized by some parents for being too dark for children and by some religious groups for its mystical elements.

Gygax credited Joseph Campbell's 1949 classic "The Hero With a Thousand Faces" for much of the inspiration for Dungeons & Dragons in the National Post interview: "The heroic quest -- the story of the hero being called forth, usually unwillingly, and adventuring and undergoing a change that has been with us probably since stories were told around campfires by men."

Born Ernest Gary Gygax in 1938, he grew up in Chicago, playing with toy soldiers and learning chess by age 6. He moved with his family to Lake Geneva at 8. Gygax's father, a Swiss immigrant who played violin in the Chicago Symphony Orchestra, read fantasy books to his only son and hooked him on the genre, Gail Gygax said.

Gygax dropped out of high school but took anthropology classes at the University of Chicago for a while, she said. He was working as an insurance underwriter in the 1960s when he began playing war-themed board games.

But Gygax wanted to create a game that involved more fantasy. To free up time to work on that, he left the insurance business and became a shoe repairman, she said.

Funeral arrangements are pending. Besides Gail Gygax, his second wife, survivors include two children from a first marriage that ended in divorce and four children from his second marriage.