One of the most prolific creators ever, Tezuka Osamu created a number of long masterworks that vary greatly in tone and content, including Phoenix, a cross-time-space oddessey, Black Jack, the story of a brilliant rogue doctor, the widely loved Astroboy, historical epics like Buddha, and many, many more. Tezuka constantly experimented with layout and storytelling techniques, but like his analogue in the film world, Akira Kurosawa, balanced experimentation with universal themes, appealing characters, and robust storytelling.
One thing that I love about Tezuka is the way his accessible, cartoonish style can carry massive epics. He blends the trivial and profound on the same page. Blah blah blah. He's a genius!