Hirokazu Yasuhara is a Japanese video game designer. He is best known for designing the gameplay and stages of the initial Sonic the Hedgehog video games for Sega Genesis in the 1990s, based on technical demos and engines programmed by Yuji Naka. "There are so many fun games nowadays. And it is getting easier to make games by using various engines and tools. But it is hard to make them “fun” without game design, like as people can’t build high risen building without architecture. I think each game designer has his or her own theory of design. So I would like to talk a part of my game design theory which is - How to make a game fun." - Hirokazu Yasuhara