 All English language versions of the game were changed from the Japanese. A  lot of the story data was left out of the English language manuals, No  mention is made of South Island or the legend behind the Chaos Emeralds, the  enemy names were all changed, Sonics small animal friends are left nameless  and ignored, and, most notoriously, Dr. Eggman was changed to Dr. Ivo  Robotnik.