Yasushi Yamaguchi

is a Japanese game designer and artist. He designed the character Miles "Tails" Prower in an internal contest hosted by Sonic Team. He originally named the character "Miles Prower", however SEGA wanted to call the character "Tails". SEGA and Yamaguchi reached a compromise on his name, with "Miles Prower" being the character's full legal name and "Tails" being his nickname.

His main work was that of both creating and designing Tails as well as being the Chief Artist and one of the Zone artists in ''Sonic the Hedgehog 2''.

He also worked as the Special Stage Designer in ''Sonic CD'' and on other Sega related games. Provided by Wikipedia