MINNEAPOLIS -- Dave Arneson, one of the co-creators of the Dungeons & Dragons fantasy game and a pioneer of role-playing entertainment, died after a two-year battle with cancer, his family said Thursday. He was 61 years old.

Mr. Arneson's daughter, Malia Weinhagen of Maplewood, said her father died peacefully Tuesday in hospice care in St. Paul. He is survived by Ms. Weinhagen and two grandchildren.

Mr. Arneson and Gary Gygax 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. It eventually was turned into video games, books and movies...