Sonic Heroes director Takashi Iizuka has spoken to Game Informer about the physical toll the game took on his general health. Iizuka explained that the level design for the Gamecube title was made by just two people and because the other developer became ill and didn’t show up for work the job was left to Iizuka alone. He explained that he was constantly in work mode and didn’t sleep and ended up losing around 22 pounds.
“The level design for Sonic Heroes was made by two people: me and one other person. As we got to the later stages of development, this other person got pretty sick and didn’t show up to work, so level design was made by one person! So for those very last stages of the game, I didn’t sleep at all and I was constantly working. I lost about [22 pounds] because I was just cranking away and it was just work, work, work. I didn’t sleep because I had to finish the game on my own. Almost dying!”