Fantasy art, that colorful blend of myth, muscle and sexy maidens, took off in 1923 with the launch of Weird Tales magazine, was reinvigorated in the 1960s with The Lord of the Rings, Conan the Barbarian paperbacks with Frank Frazetta covers, and the late '60s emergence of fantasy psychedelia. It went big in the '70s with the role-playing game Dungeons & Dragons, the brilliant French magazine M tal Hurlant, and...