Analysis of information sources in references of the Wikipedia article "Kirby's Block Ball" in English language version.
Yamagami: About 15 years ago, I worked on Kirby's Block Ball, but at first HAL Laboratory said it wasn't like Kirby. In the end, we spent about half a year on a major overhaul. They gave me thorough instruction on every aspect of Kirby's movement. ... the balance between that disciplined creativity and high degree of freedom in gameplay is the essence of Kirby.
Yamagami: About 15 years ago, I worked on Kirby's Block Ball, but at first HAL Laboratory said it wasn't like Kirby. In the end, we spent about half a year on a major overhaul. They gave me thorough instruction on every aspect of Kirby's movement. ... the balance between that disciplined creativity and high degree of freedom in gameplay is the essence of Kirby.